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 A281442 #24 Oct 21 2017 22:08:15 %S A281442 1,0,1,0,0,1,0,2,0,1,0,0,4,0,1,0,8,0,6,0,1,0,0,22,0,8,0,1,0,42,0,40,0, %T A281442 10,0,1,0,0,140,0,62,0,12,0,1,0,262,0,288,0,88,0,14,0,1,0,0,992,0,492, %U A281442 0,118,0,16,0,1 %N A281442 Triangle read by rows: T(n,r), 0 <= r <= n, is the number of idempotents of rank r in the Kauffman monoid K_n. %C A281442 Values were computed using the Semigroups package for GAP. %C A281442 T(n,r) is also the number of idempotent basis elements of rank r in the Temperley-Lieb algebra of degree n in the generic case (when the twisting parameter is not an m-th root of unity for any m <= n). %H A281442 Igor Dolinka, James East, Athanasios Evangelou, Desmond FitzGerald, Nicholas Ham, James Hyde, Nicholas Loughlin, <a href="https://arxiv.org/abs/1507.04838">Idempotent Statistics of the Motzkin and Jones Monoids</a>, arXiv:1507.04838 [math.CO], 2015-2016. %F A281442 T(2n-1,1) = A005315(n). Empirical: T(2n,2) = A077056(n); T(n+2,n-2) = 2*A028875(n) for n>2. - _Andrey Zabolotskiy_, Oct 19 2017 %Y A281442 Cf. A281438 (row sums), A281441, A289620. %K A281442 nonn,tabl %O A281442 0,8 %A A281442 _James East_, Oct 05 2017