cp's OEIS Frontend

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.

A293157 Triangle read by rows: T(n,k) = number of linear chord diagrams with n chords such that every chord has length at least k (1 <= k <= n).

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%I A293157 #26 Oct 20 2017 17:20:39
%S A293157 1,3,1,15,5,1,105,36,10,1,945,329,99,20,1,10395,3655,1146,292,40,1,
%T A293157 135135,47844,15422,4317,876,80,1,2027025,721315,237135,69862,16924,
%U A293157 2628,160,1,34459425,12310199,4106680,1251584,332507,67404,7884,320,1,654729075,234615096,79154927,24728326,6944594,1627252,269616,23652,640,1
%N A293157 Triangle read by rows: T(n,k) = number of linear chord diagrams with n chords such that every chord has length at least k (1 <= k <= n).
%C A293157 There is a surprising change in notation in Sullivan (2016) between Definition 1 and Table 1.
%C A293157 The first 11 columns are given in the reference.
%H A293157 Everett Sullivan, <a href="https://arxiv.org/abs/1611.02771">Linear chord diagrams with long chords</a>, arXiv preprint arXiv:1611.02771 [math.CO], 2016.
%e A293157 Triangle begins:
%e A293157       1;
%e A293157       3,    1;
%e A293157      15,    5,    1;
%e A293157     105,   36,   10,    1;
%e A293157     945,  329,   99,   20,    1;
%e A293157   10395, 3655, 1146,  292,   40,    1;
%e A293157   ...
%Y A293157 Cf. A000806, A001147, A190823, A190824, A190825, A020714, A278990, A293156, A293881.
%K A293157 nonn,tabl
%O A293157 1,2
%A A293157 _N. J. A. Sloane_, Oct 10 2017
%E A293157 More terms from _Alois P. Heinz_, Oct 17 2017