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 A005778 M4647 #18 Jul 08 2025 16:35:46 %S A005778 1,9,72,320,1185,3892,11776,33480,90745,236808,599112,1477216,3564001, %T A005778 8439960,19666688,45183824,102520881,230046452,511085960,1125313056, %U A005778 2457641857,5327760940,11471647872,24547187800,52225646057,110524638672 %N A005778 Rook polynomials. %D A005778 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A005778 Earl Glen Whitehead, Jr., <a href="http://dx.doi.org/10.1017/S1446788700012337">Four-discordant permutations</a>, J. Austral. Math. Soc. Ser. A 28 (1979), no. 3, 369-377. %Y A005778 A diagonal of A259985. %K A005778 nonn %O A005778 1,2 %A A005778 _N. J. A. Sloane_ %E A005778 More terms from _Sean A. Irvine_, Aug 27 2016