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 A332784 #24 Sep 26 2023 13:39:49
%S A332784 5,18,110,508,4968,25824,305376,2375616,28316832,202354752,4771240704,
%T A332784 33499830528,612464852736,9023719675392,176001733301760,
%U A332784 1649576855476224,56693983168309248,551579829498390528,20888523161929138176,342595860998544285696
%N A332784 The number of permutations of {n 1's, n 2's,...,n n's} with the property that b(1) >= b(2) >= ... >= b(n), where n k's are skipped by b(k) for k=1..n.
%F A332784 Conjecture: a(n) = A332783(n) + (n-1)!.
%e A332784 In case of n = 2.
%e A332784 | | b(1),b(2)
%e A332784 -----+--------------+----------
%e A332784 1 | [2, 2, 1, 1] | [0, 0]
%e A332784 2 | [2, 1, 2, 1] | [1, 1]
%e A332784 3 | [1, 2, 2, 1] | [2, 0]
%e A332784 4 | [1, 2, 1, 2] | [1, 1]
%e A332784 5 | [1, 1, 2, 2] | [0, 0]
%e A332784 In case of n = 3.
%e A332784 | | b(1),b(2),b(3)
%e A332784 -----+-----------------------------+---------------
%e A332784 1 | [3, 3, 3, 2, 2, 2, 1, 1, 1] | [0, 0, 0]
%e A332784 2 | [3, 3, 3, 2, 1, 2, 1, 2, 1] | [1, 1, 0]
%e A332784 3 | [3, 3, 3, 1, 2, 1, 2, 1, 2] | [1, 1, 0]
%e A332784 4 | [3, 3, 3, 1, 1, 1, 2, 2, 2] | [0, 0, 0]
%e A332784 5 | [3, 2, 1, 3, 2, 1, 3, 2, 1] | [2, 2, 2]
%e A332784 6 | [3, 1, 2, 3, 1, 2, 3, 1, 2] | [2, 2, 2]
%e A332784 7 | [1, 3, 3, 3, 1, 2, 2, 2, 1] | [3, 0, 0]
%e A332784 8 | [2, 3, 1, 2, 3, 1, 2, 3, 1] | [2, 2, 2]
%e A332784 9 | [1, 3, 2, 1, 3, 2, 1, 3, 2] | [2, 2, 2]
%e A332784 10 | [2, 1, 3, 2, 1, 3, 2, 1, 3] | [2, 2, 2]
%e A332784 11 | [1, 2, 3, 1, 2, 3, 1, 2, 3] | [2, 2, 2]
%e A332784 12 | [2, 2, 2, 3, 3, 3, 1, 1, 1] | [0, 0, 0]
%e A332784 13 | [1, 1, 1, 3, 3, 3, 2, 2, 2] | [0, 0, 0]
%e A332784 14 | [1, 2, 2, 2, 1, 3, 3, 3, 1] | [3, 0, 0]
%e A332784 15 | [2, 2, 2, 1, 1, 1, 3, 3, 3] | [0, 0, 0]
%e A332784 16 | [2, 1, 2, 1, 2, 1, 3, 3, 3] | [1, 1, 0]
%e A332784 17 | [1, 2, 1, 2, 1, 2, 3, 3, 3] | [1, 1, 0]
%e A332784 18 | [1, 1, 1, 2, 2, 2, 3, 3, 3] | [0, 0, 0]
%Y A332784 Cf. A104442, A332762, A332783, A322178, A332748, A332752, A332773.
%K A332784 nonn
%O A332784 2,1
%A A332784 _Seiichi Manyama_, Feb 23 2020
%E A332784 a(9)-a(17) from _Bert Dobbelaere_, Mar 08 2020
%E A332784 a(18)-a(21) from _Max Alekseyev_, Sep 26 2023