jakedobkin

#!/usr/local/bin/node

// calculate the decimal to 1MM places, but record certain values

string = "";
for (i=1;i<=1000000;i++)
	{
		string += i.toString()
	}

jakedobkin

#!/usr/local/bin/node

// first, prep prime seive up to 7654321, which is the largest pan that doesn't fail the 
// summing divisibility rules for 3 or 9 

n=7654321;
myPrimes = new Array();
for (i=2;i<=n;i++)
	{
	myPrimes[i]=true;

jakedobkin

#!/usr/local/bin/node

words = ["A","ABILITY","ABLE","ABOUT","ABOVE","ABSENCE","ABSOLUTELY","ACADEMIC","ACCEPT","ACCESS","ACCIDENT","ACCOMPANY","ACCORDING","ACCOUNT","ACHIEVE","ACHIEVEMENT","ACID","ACQUIRE","ACROSS","ACT","ACTION","ACTIVE","ACTIVITY","ACTUAL","ACTUALLY","ADD","ADDITION","ADDITIONAL","ADDRESS","ADMINISTRATION","ADMIT","ADOPT","ADULT","ADVANCE","ADVANTAGE","ADVICE","ADVISE","AFFAIR","AFFECT","AFFORD","AFRAID","AFTER","AFTERNOON","AFTERWARDS","AGAIN","AGAINST","AGE","AGENCY","AGENT","AGO","AGREE","AGREEMENT","AHEAD","AID","AIM","AIR","AIRCRAFT","ALL","ALLOW","ALMOST","ALONE","ALONG","ALREADY","ALRIGHT","ALSO","ALTERNATIVE","ALTHOUGH","ALWAYS","AMONG","AMONGST","AMOUNT","AN","ANALYSIS","ANCIENT","AND","ANIMAL","ANNOUNCE","ANNUAL","ANOTHER","ANSWER","ANY","ANYBODY","ANYONE","ANYTHING","ANYWAY","APART","APPARENT","APPARENTLY","APPEAL","APPEAR","APPEARANCE","APPLICATION","APPLY","APPOINT","APPOINTMENT","APPROACH","APPROPRIATE","APPROVE","AREA","ARGUE","ARGUMENT","ARISE","ARM","ARMY","AROUND","ARRANG

jakedobkin

# let's try using the built in permutation function!

import itertools
x = itertools.permutations('0123456789', 10)

sum = 0

for i in x:
	string= "".join(list(i))
	number = int(string)

jakedobkin

# let's start by making a set of all pentagonal numbers from to n=10000 
# you can actually do to like n=4000 and get the same answer
# then let's say check every number in set vs. every other.  
# if sum and difference is also in the set, compute the difference, print

h = set()

for i in range (1,10000):
	pent = (i*(3*i-1))/2
	h.add(pent)

jakedobkin

# we'll store numbers in two sets and keep going until we get a match

i = 286
found = False
p = set()
h = set()

while found == False:
	hex = (i*(2*i-1))
	h.add(hex)

jakedobkin

# set up prime seive
n=10000
myPrimes = []
myPrimes = [True]*10001
myPrimes[0] = False
myPrimes[1] = False
for i in range (2,n):
	if myPrimes[i] == True:
		j = 2*i
		while j<=n:

jakedobkin

# set up 2 sieves- one is erastosthenes, the other is to track count
n=200000
myPrimes = [True]*(n+1)
myCount = [0]*(n+1)

# sieve, but count each time each composite number is hit during sieve 
for i in range (2,n):
	if myPrimes[i] == True:
		j = 2*i
		while j<=n:

jakedobkin

# http://projecteuler.net/problem=48. 

n = 1000
sum = 0
for i in range (1,n+1):
	sum += i**i
	
print str(sum)[-10:]

# python makes this trivial- but for a language that can't deal with large numbers,

jakedobkin

# http://projecteuler.net/problem=49

# we'll use the python built-in permutation function
import itertools

# prime sieve
n=100000
myPrimes = [True]*(n+1)
for i in range (2,n):
	if myPrimes[i] == True: