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 A321669 #15 Nov 10 2024 21:46:28 %S A321669 1,0,1,2872754,104650147201049,23575497690601916022516, %T A321669 24302858067615766089801166488125, %U A321669 91155245844064069307740171414201519055298,1046031892354833895113128900608177633584652958677057,32119646666355552112999645991677870426882424139287301894021793 %N A321669 Number of permutations of 9 copies of 1..n introduced in order 1..n with no element equal to another within a distance of 1. %H A321669 Seiichi Manyama, <a href="/A321669/b321669.txt">Table of n, a(n) for n = 0..70</a> %F A321669 a(n) ~ 9^(7*n + 1/2) * n^(8*n) / (4480^n * exp(8*(n+1))). - _Vaclav Kotesovec_, Nov 24 2018 %Y A321669 Row n=9 of A322013. %Y A321669 Cf. A190826, A190830, A190833, A190835, A190836, A190837, A321670. %K A321669 nonn %O A321669 0,4 %A A321669 _Seiichi Manyama_, Nov 16 2018