diff --git a/superelliptic.ipynb b/superelliptic.ipynb
index 22d0da3..0d1accf 100644
--- a/superelliptic.ipynb
+++ b/superelliptic.ipynb
@@ -2,9 +2,22 @@
  "cells": [
   {
    "cell_type": "code",
-   "execution_count": 219,
+   "execution_count": 87,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "ename": "NameError",
+     "evalue": "name 'holo' is not defined",
+     "output_type": "error",
+     "traceback": [
+      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
+      "\u001b[0;31mNameError\u001b[0m                                 Traceback (most recent call last)",
+      "\u001b[0;32m<ipython-input-87-fb238ae380ad>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0;32mclass\u001b[0m \u001b[0msuperelliptic\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      2\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0m__init__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mf\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mm\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mp\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      3\u001b[0m         \u001b[0mR\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mPolynomialRing\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mGF\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mp\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mnames\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'x'\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m;\u001b[0m \u001b[0;34m(\u001b[0m\u001b[0mx\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m)\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mR\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_first_ngens\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m         \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mpolynomial\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mR\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mf\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      5\u001b[0m         \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mexponent\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mm\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;32m<ipython-input-87-fb238ae380ad>\u001b[0m in \u001b[0;36msuperelliptic\u001b[0;34m()\u001b[0m\n\u001b[1;32m     53\u001b[0m             \u001b[0;32mfor\u001b[0m \u001b[0mj\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mInteger\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m1\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mm\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m     54\u001b[0m                 \u001b[0mholo\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mbaza_holo\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mm\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mf\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mj\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mp\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m---> 55\u001b[0;31m     \u001b[0;32mfor\u001b[0m \u001b[0mk\u001b[0m \u001b[0;32min\u001b[0m \u001b[0mrange\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mInteger\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;36m0\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mlen\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mholo\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m     56\u001b[0m         \u001b[0mbaza\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mk\u001b[0m\u001b[0;34m]\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mholo\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mk\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m     57\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;31mNameError\u001b[0m: name 'holo' is not defined"
+     ]
+    }
+   ],
    "source": [
     "class superelliptic:\n",
     "    def __init__(self, f, m, p):\n",
@@ -13,7 +26,6 @@
     "        self.exponent = m\n",
     "        self.characteristic = p\n",
     "        \n",
-    "       \n",
     "    def __repr__(self):\n",
     "        f = self.polynomial\n",
     "        m = self.exponent\n",
@@ -36,8 +48,8 @@
     "        basis = {}\n",
     "        if j == 'all':\n",
     "            k = 0\n",
-    "            for i in range(1, r):\n",
-    "                for j in range(1, m):\n",
+    "            for j in range(1, m):\n",
+    "                for i in range(1, r):\n",
     "                    if (r*j - m*i >= delta):\n",
     "                        basis[k] = superelliptic_form(C, x^(i-1)/y^j)\n",
     "                        k = k+1\n",
@@ -49,7 +61,21 @@
     "                    basis[k] = superelliptic_form(C, x^(i-1)/y^j)\n",
     "                    k = k+1\n",
     "            return basis\n",
-    "        \n",
+    "     \n",
+    "    def basis_de_rham(self, j = 'all'):\n",
+    "        f = self.polynomial\n",
+    "        m = self.exponent\n",
+    "        p = self.characteristic\n",
+    "        r = f.degree()\n",
+    "        delta = GCD(r, m)\n",
+    "        #?????\n",
+    "        basis = {}\n",
+    "        if j == 'all':\n",
+    "            for j in range(1, m):\n",
+    "                holo = baza_holo(m, f, j, p)\n",
+    "    for k in range(0, len(holo)):\n",
+    "        baza[k] = holo[k]\n",
+    "    \n",
     "def reduction(C, g):\n",
     "    p = C.characteristic\n",
     "    R.<x, y> = PolynomialRing(GF(p), 2)\n",
@@ -69,7 +95,7 @@
     "    \n",
     "    while(g.degree(R(y)) >= m):\n",
     "        d = g.degree(R(y))\n",
-    "        G = g.coefficient(R(y^d))\n",
+    "        G = coff(g, d)\n",
     "        i = floor(d/m)\n",
     "        g = g - G*y^d + f^i * y^(d%m) *G\n",
     "    \n",
@@ -91,9 +117,12 @@
     "    \n",
     "    g = R3(g)\n",
     "    for j in range(0, m):\n",
-    "        G = g.coefficients(sparse = false)[j]\n",
-    "        g1 += RR(y^(j-m)*f*G)\n",
-    "        \n",
+    "        if j==0:\n",
+    "            G = coff(g, 0)\n",
+    "            g1 += G\n",
+    "        else:\n",
+    "            G = coff(g, j)\n",
+    "            g1 += RR(y^(j-m)*f*G)\n",
     "    return(g1)\n",
     "        \n",
     "class superelliptic_function:\n",
@@ -184,55 +213,128 @@
     "    \n",
     "    def jth_component(self, j):\n",
     "        g = self.form\n",
-    "        R.<x, y> = PolynomialRing(GF(p), 2)\n",
-    "        g = R(g)\n",
-    "        return g.coefficient(y^j)"
+    "        R1.<x> = PolynomialRing(GF(p))\n",
+    "        R2 = FractionField(R1)\n",
+    "        R3.<y> = PolynomialRing(R2)\n",
+    "        R4 = FractionField(R3)\n",
+    "        R5.<y_inv> = PolynomialRing(R2)\n",
+    "        g = R4(g)\n",
+    "        g = g(y = 1/y_inv)\n",
+    "        g = R5(g)\n",
+    "        return coff(g, j)\n",
+    "    \n",
+    "    def is_regular_on_U0(self):\n",
+    "        C = self.curve\n",
+    "        p = C.characteristic\n",
+    "        m = C.exponent\n",
+    "        R.<x> = PolynomialRing(GF(p))\n",
+    "        for j in range(1, m):\n",
+    "            if self.jth_component(j) not in R:\n",
+    "                return 0\n",
+    "        return 1\n",
+    "    \n",
+    "    def is_regular_on_Uinfty(self):\n",
+    "        C = self.curve\n",
+    "        p = C.characteristic\n",
+    "        m = C.exponent\n",
+    "        f = C.polynomial\n",
+    "        r = f.degree()\n",
+    "        delta = GCD(m, r)\n",
+    "        M = m/delta\n",
+    "        R = r/delta\n",
+    "        \n",
+    "        for j in range(1, m):\n",
+    "            A = self.jth_component(j)\n",
+    "            d = degree_of_rational_fctn(A)\n",
+    "            if(-d*M + j*R -(M+1)<0):\n",
+    "                return 0\n",
+    "        return 1\n",
+    "    \n",
+    "class superelliptic_cech:\n",
+    "    def __init__(self, omega, fct):\n",
+    "        self.omega0 = omega\n",
+    "        self.omega8 = omega - diffn(fct)\n",
+    "        self.f = fct\n",
+    "        \n",
+    "def degree_of_rational_fctn(f):\n",
+    "    R.<x> = PolynomialRing(GF(p))\n",
+    "    RR = FractionField(R)\n",
+    "    f = RR(f)\n",
+    "    f1 = f.numerator()\n",
+    "    f2 = f.denominator()\n",
+    "    d1 = f1.degree()\n",
+    "    d2 = f2.degree()\n",
+    "    return(d1 - d2)\n",
+    "\n",
+    "def coff(f, d):\n",
+    "    lista = f.coefficients(sparse = false)\n",
+    "    if len(lista) <= d:\n",
+    "        return 0\n",
+    "    return lista[d]\n",
+    "\n",
+    "def cut(f, i):\n",
+    "    coeff = f.coefficients(sparse = false)\n",
+    "    return sum(x^(j-i-1) * coeff[j] for j in range(i+1, f.degree() + 1))"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 220,
+   "execution_count": 80,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "{0: (1/y) dx}"
+       "((-2*x^3*y + x^2 + x)/y) dx"
       ]
      },
-     "execution_count": 220,
+     "execution_count": 80,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
     "C = superelliptic(x^3 + x + 2, 2, 5)\n",
-    "C.basis_holomorphic_differentials()"
+    "omega = superelliptic_form(C, (x^2+x)/y + 3*x^3)\n",
+    "omega"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 179,
+   "execution_count": 81,
    "metadata": {},
    "outputs": [
     {
-     "data": {
-      "text/plain": [
-       "0"
-      ]
-     },
-     "execution_count": 179,
-     "metadata": {},
-     "output_type": "execute_result"
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "(1/y) dx\n",
+      "1 1\n",
+      "{0: (1/y) dx}\n"
+     ]
     }
    ],
    "source": [
-    "A.degree(y)"
+    "licz = 0\n",
+    "m = 2\n",
+    "p = 5\n",
+    "R1.<x> = PolynomialRing(GF(p))\n",
+    "f = R1(x^3 + x + 4)\n",
+    "r = f.degree()\n",
+    "C = superelliptic(f, m, p)\n",
+    "for i in range(0, r):\n",
+    "    for j in range(1, m):\n",
+    "        omega = superelliptic_form(C, x^i/y^j)\n",
+    "        if (omega.is_regular_on_U0() and omega.is_regular_on_Uinfty()):\n",
+    "            print(omega)\n",
+    "            licz += 1\n",
+    "print(licz, C.genus())\n",
+    "print(C.basis_holomorphic_differentials())"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 180,
+   "execution_count": 82,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -243,7 +345,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 181,
+   "execution_count": 83,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -252,16 +354,16 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 183,
+   "execution_count": 84,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "-2*x^2 + 1"
+       "3*x^2 + 1"
       ]
      },
-     "execution_count": 183,
+     "execution_count": 84,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -272,7 +374,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 33,
+   "execution_count": 85,
    "metadata": {},
    "outputs": [
     {
@@ -281,7 +383,7 @@
        "y"
       ]
      },
-     "execution_count": 33,
+     "execution_count": 85,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -299,7 +401,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 39,
+   "execution_count": 86,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -357,34 +459,81 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 213,
+   "execution_count": 3,
    "metadata": {},
    "outputs": [],
    "source": [
+    "p = 5\n",
     "R1.<x> = PolynomialRing(GF(p))\n",
     "R2 = FractionField(R1)\n",
     "R3.<y> = PolynomialRing(R2)\n",
-    "g = y^2/x + y/(x+1)    "
+    "g = y^2/x + y/(x+1)    \n",
+    "g = 1/y+x/y^2"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 218,
+   "execution_count": 4,
    "metadata": {},
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "[0, 1/(x + 1), 1/x]"
+       "x*z^2 + z"
       ]
      },
-     "execution_count": 218,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "g.coefficients(sparse = false)"
+    "R3.<z> = PolynomialRing(R2)\n",
+    "g(y = 1/z)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 57,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "x^3 + x + 4"
+      ]
+     },
+     "execution_count": 57,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "f"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 62,
+   "metadata": {},
+   "outputs": [
+    {
+     "ename": "AttributeError",
+     "evalue": "'sage.rings.polynomial.polynomial_zmod_flint.Polynomial_zmod_flint' object has no attribute 'coefficient'",
+     "output_type": "error",
+     "traceback": [
+      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
+      "\u001b[0;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
+      "\u001b[0;32m<ipython-input-62-e054c182ec1a>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m()\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mf\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcoefficient\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
+      "\u001b[0;32m/opt/sagemath-9.1/local/lib/python3.7/site-packages/sage/structure/element.pyx\u001b[0m in \u001b[0;36msage.structure.element.Element.__getattr__ (build/cythonized/sage/structure/element.c:4614)\u001b[0;34m()\u001b[0m\n\u001b[1;32m    485\u001b[0m             \u001b[0mAttributeError\u001b[0m\u001b[0;34m:\u001b[0m \u001b[0;34m'LeftZeroSemigroup_with_category.element_class'\u001b[0m \u001b[0mobject\u001b[0m \u001b[0mhas\u001b[0m \u001b[0mno\u001b[0m \u001b[0mattribute\u001b[0m \u001b[0;34m'blah_blah'\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    486\u001b[0m         \"\"\"\n\u001b[0;32m--> 487\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mgetattr_from_category\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mname\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    488\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    489\u001b[0m     \u001b[0mcdef\u001b[0m \u001b[0mgetattr_from_category\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mname\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;32m/opt/sagemath-9.1/local/lib/python3.7/site-packages/sage/structure/element.pyx\u001b[0m in \u001b[0;36msage.structure.element.Element.getattr_from_category (build/cythonized/sage/structure/element.c:4723)\u001b[0;34m()\u001b[0m\n\u001b[1;32m    498\u001b[0m         \u001b[0;32melse\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    499\u001b[0m             \u001b[0mcls\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mP\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_abstract_element_class\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 500\u001b[0;31m         \u001b[0;32mreturn\u001b[0m \u001b[0mgetattr_from_other_class\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mcls\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mname\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    501\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    502\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0m__dir__\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;32m/opt/sagemath-9.1/local/lib/python3.7/site-packages/sage/cpython/getattr.pyx\u001b[0m in \u001b[0;36msage.cpython.getattr.getattr_from_other_class (build/cythonized/sage/cpython/getattr.c:2614)\u001b[0;34m()\u001b[0m\n\u001b[1;32m    392\u001b[0m         \u001b[0mdummy_error_message\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcls\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mtype\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    393\u001b[0m         \u001b[0mdummy_error_message\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mname\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mname\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 394\u001b[0;31m         \u001b[0;32mraise\u001b[0m \u001b[0mAttributeError\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mdummy_error_message\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    395\u001b[0m     \u001b[0mattribute\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m<\u001b[0m\u001b[0mobject\u001b[0m\u001b[0;34m>\u001b[0m\u001b[0mattr\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    396\u001b[0m     \u001b[0;31m# Check for a descriptor (__get__ in Python)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;31mAttributeError\u001b[0m: 'sage.rings.polynomial.polynomial_zmod_flint.Polynomial_zmod_flint' object has no attribute 'coefficient'"
+     ]
+    }
+   ],
+   "source": [
+    "f.coefficient()"
    ]
   },
   {