yaworsw/euler-manager

---
:id: 340
:name: Crazy Function
:url: https://projecteuler.net/problem=340
:content: "For fixed integers a, b, c, define the _crazy function_ F(<var>n</var>)
  as follows:  \nF(<var>n</var>) = <var>n</var> - c for all <var>n</var> \\> b   \nF(<var>n</var>)
  = F(a + F(a + F(a + F(a + <var>n</var>)))) for all <var>n</var> ≤ b.\n\nAlso, define
  S(a, b, c) = ![p340_formula.gif]({{ images_dir }}/p340_formula.gif).\n\nFor example,
  if a = 50, b = 2000 and c = 40, then F(0) = 3240 and F(2000) = 2040.  \nAlso, S(50,
  2000, 40) = 5204240.\n\nFind the last 9 digits of S(21<sup>7</sup>, 7<sup>21</sup>,
  12<sup>7</sup>).\n\n"