find largest divisor & find sum of odd squares
fixed my work when I saw my answer was wrong from LYAH. I was incorrectly calculating the sum of sumSquares [1..n] where n would begin at 1. So I was summing over [1 (1^2), 1 (1^2), 10 (1^2 + 3^2), ...].
added LYAH version of SumOddSquaresLt10k
added collatz function
added to LYAH's version of sumOddSquares