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{
"cells": [
{
"cell_type": "code",
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
"from math import factorial\n",
"import numpy as np\n",
"\n",
"# Quick sieve of Eratosthenes\n",
"P=np.zeros(10000)\n",
"P[0]=1\n",
"P[1]=1\n",
"for i in range(2,10000):\n",
" if P[i]==0:\n",
" j=2\n",
" while i*j<1000:\n",
" P[i*j]=1\n",
" j=j+1\n",
"\n",
"Primes10000=[i for i,x in enumerate(P) if x==0]\n",
"\n",
"def mexp(a,x,N):\n",
" m,s=1,a\n",
" while x>0:\n",
" if x % 2 ==1:\n",
" m=((m*s) % N)\n",
" s=((s*s) % N)\n",
" x=x//2\n",
" return m\n",
"\n",
"def euclid(u,v):\n",
" if v==0:\n",
" raise ArithmeticError('Division by Zero')\n",
" x0,x1=u,v\n",
" a0,a1=1,0\n",
" b0,b1=0,1\n",
" while x1!=0:\n",
" q=x0//x1\n",
" x2=x0-q*x1\n",
" a2=a0-q*a1\n",
" b2=b0-q*b1\n",
" x0,a0,b0=x1,a1,b1\n",
" x1,a1,b1=x2,a2,b2\n",
" if x0<0:\n",
" return -x0,-a0,-b0\n",
" else:\n",
" return x0,a0,b0\n",
"\n",
"def show_factors(N):\n",
" for x in Primes10000:\n",
" while N % x ==0:\n",
" print(x)\n",
" N=N//x\n",
" if N==1:\n",
" break\n",
" "
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"1869036133\n"
]
},
{
"data": {
"text/plain": [
"(641, -1415069, 615794)"
]
},
"execution_count": 3,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"N=2**32+1\n",
"T=mexp(5,factorial(10),N)-1\n",
"print(T)\n",
"euclid(T,N)"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"3\n",
"3\n",
"5\n",
"7\n",
"--\n",
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"2\n",
"5\n"
]
}
],
"source": [
"show_factors(factorial(8))\n",
"print('--')\n",
"show_factors(640)"
]
},
{
"cell_type": "code",
"execution_count": 20,
"metadata": {},
"outputs": [
{
"name": "stdout",
"output_type": "stream",
"text": [
"189001559038533300097388655917426122707\n"
]
},
{
"data": {
"text/plain": [
"(1,\n",
" 3112174408228168112550962732800696651,\n",
" -1728581532088651726610480563918521808)"
]
},
"execution_count": 20,
"metadata": {},
"output_type": "execute_result"
}
],
"source": [
"N=2**128+1\n",
"T=mexp(3,factorial(500),N)-1\n",
"print(T)\n",
"euclid(T,N)"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {},
"outputs": [],
"source": []
}
],
"metadata": {
"kernelspec": {
"display_name": "Python 3",
"language": "python",
"name": "python3"
},
"language_info": {
"codemirror_mode": {
"name": "ipython",
"version": 3
},
"file_extension": ".py",
"mimetype": "text/x-python",
"name": "python",
"nbconvert_exporter": "python",
"pygments_lexer": "ipython3",
"version": "3.6.5"
}
},
"nbformat": 4,
"nbformat_minor": 2
}