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 A343488 #8 Apr 18 2021 09:04:00 %S A343488 1,1,2,0,3,0,3,4,4,0,16,5,0,0,0,115,6,12,42,0,0,660,7,0,0,0,0,0,5033, %T A343488 8,24,0,352,0,0,0,39936,9,0,153,0,0,0,0,0,362718,10,40,0,0,3830,0,0,0, %U A343488 0,3624920,11,0,0,0,0,0,0,0,0,0,39916789,12,60,372,1872,0,45636,0,0,0,0,0,478953648 %N A343488 Irregular table T(n, k), n >= 0, k = 1..max(1, n), read by rows; T(n, k) is the number of permutations s of { 1..n } such that p(s) = k where p(s) is the least m > 0 such that, working in Z/nZ, s(i) + m = s(i + m) for i = 1..n. %C A343488 We set the row for n = 0 to [1] by convention. %C A343488 The number p(s) can be interpreted as the period of the permutation s. %H A343488 Igor Pak, <a href="https://www.math.ucla.edu/~pak/papers/inf2.pdf">Periodic permutations and the Robinson-Schensted correspondence</a> %H A343488 Rémy Sigrist, <a href="/A343488/a343488.txt">C program for A343488</a> %H A343488 <a href="https://oeis.org/index/Per#perm">Index entries for sequences related to permutations</a> %F A343488 T(n, 1) = max(n, 1). %F A343488 T(n, n) = A324514(n). %F A343488 Sum_{k = 1..max(1, n)} T(n, k) = n!. %e A343488 Table begins: %e A343488 0: [1] %e A343488 1: [1] %e A343488 2: [2, 0] %e A343488 3: [3, 0, 3] %e A343488 4: [4, 4, 0, 16] %e A343488 5: [5, 0, 0, 0, 115] %e A343488 6: [6, 12, 42, 0, 0, 660] %e A343488 7: [7, 0, 0, 0, 0, 0, 5033] %e A343488 8: [8, 24, 0, 352, 0, 0, 0, 39936] %e A343488 9: [9, 0, 153, 0, 0, 0, 0, 0, 362718] %e A343488 10: [10, 40, 0, 0, 3830, 0, 0, 0, 0, 3624920] %o A343488 (C) See Links section. %Y A343488 Cf. A000142, A324514. %K A343488 nonn,tabf %O A343488 0,3 %A A343488 _Rémy Sigrist_, Apr 17 2021