%I #13 Oct 15 2020 16:34:43
%S 1,4,7,26,68,75,236,940,1090,1105,2752,16645,20360,20790,20821,39208,
%T 360081,464111,477242,478376,478439,660032,9202170,12492277,12933423,
%U 12974826,12977688,12977815
%N Triangle read by rows: number of generic n-rook placements with k rooks below the main diagonal.
%H 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 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 Triangle begins:
%e 1,
%e 4,7,
%e 26,68,75,
%e 236,940,1090,1105,
%e 2752,16645,20360,20790,20821,
%e 39208,360081,464111,477242,478376,478439,
%e 660032,9202170,12492277,12933423,12974826,12977688,12977815,
%e ...
%K nonn,tabl,more
%O 1,2
%A _N. J. A. Sloane_, Mar 16 2016