For those who are wondering, the price in hearts of super nymph slots goes 1, 2, 5, 10, 25. I'm not sure about the last slot, as I can't see the price of the sixth until I buy the fifth. The online encyclopedia of integer sequences suggests 50 as the next number:

http://oeis.org/search?q=1%2C2%2C5%2...lish&go=Search

It finds six sequences that have 1,2,5,10,25, and four of them have 50 as their next value. The other next values suggested are 48 and 58, neither of which I regard as likely.

For comparison, the levels of fanny magnet start as 1,2,3--in particular, 3 hearts for the third level, not 5. That is not enough of a sequence to meaningfully consult the OEIS.