vlad8's blog

By vlad8, history, 8 years ago, translation, In English

Hello, Codeforces!
There is a task, equivalent to the following equation:
Fn % n = 0 && F(n+1) % n = 1, n is N
Here Fn is nth Fibonacci number, F1 = F2 = 1.
Python gives next solutions {24, 48, 72, 96, 120, 144, 192, 216, 240, 288, 336, 360, 384, 432, 480, 576, 600, 648, 672, 720, 768, 864, 960, 1008, 1080, 1104, 1152, 1200, 1224, 1296, 1320, 1344, 1368, 1440, 1536, 1680, 1728, 1800, 1920, 1944, 2016, 2160, 2208, 2304, 2352, 2400, 2448, 2592, 2640, 2688, 2736, 2880, 3000, 3024, 3072, 3240, 3312, 3360 ... }, but all clear is that them all are 24*k.
Does someone has any ideas how to solve it?
Thanks in advance!

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