euler-012-highly-divisible-triangular-number-20130725.ipynb

{
 "metadata": {
  "name": "euler-012-highly-divisible-triangular-number-20130725"
 },
 "nbformat": 3,
 "nbformat_minor": 0,
 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from euler import gen_triangular\n",
      "from euler import gen_lt\n",
      "from euler import get_factors\n",
      "from euler import product"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 1
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "list(gen_lt(gen_triangular(), 100))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "pyout",
       "prompt_number": 2,
       "text": [
        "[1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91]"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def terse(x):\n",
      "    f = {}\n",
      "    for i in x:\n",
      "        if i not in f:\n",
      "            f[i] = 0\n",
      "        f[i] += 1\n",
      "    return f"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 3
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "def foo(n):\n",
      "    for t in gen_triangular():\n",
      "        if product(map((lambda x: x+1), terse(get_factors(t)).values())) > n:\n",
      "            return t"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 4
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "n = 500\n",
      "%timeit foo(n)\n",
      "foo(n)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "1 loops, best of 3: 1.03 s per loop\n"
       ]
      },
      {
       "output_type": "pyout",
       "prompt_number": 5,
       "text": [
        "76576500"
       ]
      }
     ],
     "prompt_number": 5
    }
   ],
   "metadata": {}
  }
 ]
}