First solution in Go.
Second go solution.
Fibonacci solution.
start of one approach.
Approach 2. Time for bed.
Start prime factoring again.
GCD
Palindromic numbers.
Smallest multiple.
Sum square difference. Wat?
Primes.
Largest product in a series.
Pythagoreans.
Prime sieve using a dict to keep track of known prime multiples which we haven't tested yet.
Number grid.
Naive divisor calculator of triangular numbers.
Number of divisors. Hacky.
collatz
Summing large numbers. Need to work out error.
lattice paths