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 A269744 #13 Oct 15 2020 16:34:43 %S A269744 1,4,7,26,68,75,236,940,1090,1105,2752,16645,20360,20790,20821,39208, %T A269744 360081,464111,477242,478376,478439,660032,9202170,12492277,12933423, %U A269744 12974826,12977688,12977815 %N A269744 Triangle read by rows: number of generic n-rook placements with k rooks below the main diagonal. %H A269744 E. Banaian, S. Butler, C. Cox, J. Davis, J. Landgraf and S. Ponce, <a href="http://arxiv.org/abs/1508.03673">A generalization of Eulerian numbers via rook placements</a>, arXiv:1508.03673 [math.CO], 2015. %H A269744 A. N. Bhavale, B. N. Waphare, <a href="https://ajc.maths.uq.edu.au/pdf/78/ajc_v78_p073.pdf">Basic retracts and counting of lattices</a>, Australasian J. of Combinatorics (2020) Vol. 78, No. 1, 73-99. %e A269744 Triangle begins: %e A269744 1, %e A269744 4,7, %e A269744 26,68,75, %e A269744 236,940,1090,1105, %e A269744 2752,16645,20360,20790,20821, %e A269744 39208,360081,464111,477242,478376,478439, %e A269744 660032,9202170,12492277,12933423,12974826,12977688,12977815, %e A269744 ... %K A269744 nonn,tabl,more %O A269744 1,2 %A A269744 _N. J. A. Sloane_, Mar 16 2016