data/problems/271.yml
---
:id: 271
:name: Modular Cubes, part 1
:url: https://projecteuler.net/problem=271
:content: "For a positive number <var>n</var>, define S(<var>n</var>) as the sum of
the integers <var>x,</var> for which 1\\<<var>x</var>\\<<var>n</var> and \n<var>x</var><sup>3</sup>≡1
mod <var>n</var>.\n\nWhen <var>n</var>=91, there are 8 possible values for <var>x</var>,
namely : 9, 16, 22, 29, 53, 74, 79, 81. \nThus, S(91)=9+16+22+29+53+74+79+81=363.\n\nFind
S(13082761331670030).\n\n"