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 A171906 #4 Jul 22 2025 07:32:14 %S A171906 44,45,20,10,0,1 %N A171906 a(n) = number of 5 X 5 permutation matrices with trace n. %e A171906 a(0)=44 because we have 44 different permutation matrices 5 x 5 with trace 0. %Y A171906 A171806, A171808, A171809, A171907, A171908 %K A171906 nonn %O A171906 0,1 %A A171906 _Artur Jasinski_, Dec 31 2009