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 A243834 #8 Feb 03 2019 07:38:30 %S A243834 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, %T A243834 0,0,0,0,0,0,0,0,0,0,1430,0,0,0,0,0,0,0,0,1430,0,0,0,0,0,0,0,0,0,1,0, %U A243834 0,0,0,0,0,0,0,0,0,0,36,0,0,0,0,0,0,0,0,0,0,0,1,540,0,0,0,0,0,0,0,0,0,0,0,0,45,4950,0,0 %N A243834 Number A(n,k) of Dyck paths of semilength n having exactly eight (possibly overlapping) occurrences of the consecutive step pattern given by the binary expansion of k, where 1=U=(1,1) and 0=D=(1,-1); square array A(n,k), n>=0, k>=0, read by antidiagonals. %H A243834 Alois P. Heinz, <a href="/A243834/b243834.txt">Antidiagonals n = 0..140, flattened</a> %e A243834 Square array A(n,k) begins: %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 1430, 1430, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ... %e A243834 0, 0, 36, 1, 0, 1, 0, 0, 0, 0, 1, 0, ... %e A243834 0, 0, 540, 45, 0, 9, 0, 1, 0, 0, 1, 0, ... %e A243834 0, 0, 4950, 825, 0, 90, 0, 11, 0, 0, 19, 0, ... %Y A243834 Main diagonal gives A243777 or column k=8 of A243752. %Y A243834 Cf. A243753, A243827, A243828, A243829, A243830, A243831, A243832, A243833, A243835, A243836. %K A243834 nonn,tabl %O A243834 0,45 %A A243834 _Alois P. Heinz_, Jun 11 2014