This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A257961 #18 Jun 16 2015 13:27:20 %S A257961 0,0,1,0,2,1,0,3,1,4,2,0,5,2,7,4,1,6,3,0,8,3,11,6,1,9,4,12,7,2,10,5,0, %T A257961 13,5,18,10,2,15,7,20,12,4,17,9,1,14,6,19,11,3,16,8,0,21,8,29,16,3,24, %U A257961 11,32,19,6,27,14,1,22,9,30,17,4,25,12,33,20,7 %N A257961 List of permutations of the intervals of numbers [0,F(n)) defined by x -> x*F(n-1) mod F(n), where F(n) is the n-th Fibonacci number A000045. %C A257961 This sequence divides into blocks of length F(n), n = 2, 3, 4, 5, 6, ... (so F(n) = 1, 2, 3, 5, 8, ...) %H A257961 Peter G. Anderson, <a href="/A257961/b257961.txt">Table of n, a(n) for n = 0..317808</a> %e A257961 This is an irregular array, the first few rows of which are: %e A257961 0; %e A257961 0, 1; %e A257961 0, 2, 1; %e A257961 0, 3, 1, 4, 2; %e A257961 0, 5, 2, 7, 4, 1, 6, 3; %e A257961 0, 8, 3, 11, 6, 1, 9, 4, 12, 7, 2, 10, 5; %e A257961 0, 13, 5, 18, 10, 2, 15, 7, 20, 12, 4, 17, 9, 1, 14, 6, 19, 11, 3, 16, 8; %o A257961 (PARI) row(n) = if (n<=2, [0], vector(fibonacci(n), k, (k-1)*fibonacci(n-1) % fibonacci(n))); \\ _Michel Marcus_, May 28 2015 %K A257961 nonn,tabf %O A257961 0,5 %A A257961 _Peter G. Anderson_, May 14 2015