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 A350041 #25 Dec 20 2021 02:01:23 %S A350041 1,1,1,1,5,3,1,45,29,6,807,422,46,20022,8270,424,642162,211848 %N A350041 Number of ways of placing maximum number of nonattacking rooks on a triangular board with edge-length n (symmetric solutions count only once). %C A350041 The rooks placements are considered different when they cannot be obtained by a rotation and/or reflection of another solution that leaves the board inchanged. - _Alain Brobecker_, Dec 19 2021 %C A350041 a(n) = A350191(n) for n <> 10,13,16,19,... - _Vaclav Kotesovec_, Dec 20 2021 %H A350041 Alain Brobecker, <a href="http://abrobecker.free.fr/text/NonAttackingRooks.pdf">Non Attacking Rooks on Hexhex and Triangular boards</a> %Y A350041 Cf. A004396, A289893, A350191. %K A350041 nonn,more,hard %O A350041 1,5 %A A350041 _Alain Brobecker_, Dec 10 2021 %E A350041 a(17)-a(18) from _Vaclav Kotesovec_, Dec 19 2021