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 A122823 #2 Mar 31 2012 20:25:47 %S A122823 2,7,11,15,96,132,26,378,2088,2664,40,1040,12960,66240,80640,57,2325, %T A122823 51600,594000,2894400,3412800,77,4536,157500,3225600,35380800, %U A122823 166924800,192326400,100,8036,402192,12877200,251193600,2667168000,12294374400 %N A122823 Triangle read by rows: T(n,k) = count of increasing runs in two concatenated k-permutations of [n]. %F A122823 T(n,k) = ((k+1) - (n-1)/2n) * Permute(n,k)^2 %e A122823 Triangle begins: %e A122823 2 %e A122823 7 11 %e A122823 15 96 132 %e A122823 Take the 2-permutations of [2] namely 12 and 21 and form all possible strings that are concatenations of two of these permutations. These are 1212,1221,2112,2121 with 2,3,3,3 increasing runs respectively. T(2,2) = 2+3+3+3 = 11. %Y A122823 Column 1 = T(n, 1) = A005449, Second pentagonal numbers: n*(3n+1)/2. %K A122823 easy,nonn,tabl %O A122823 1,1 %A A122823 _David Scambler_, Oct 29 2006