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 A195827 #12 Mar 30 2012 17:34:07 %S A195827 0,1,2,3,0,4,1,5,2,6,3,0,7,4,1,8,5,2,9,6,3,10,7,4,11,8,5,12,9,6,0,13, %T A195827 10,7,1,14,11,8,2,15,12,9,3,16,13,10,4,17,14,11,5,0,18,15,12,6,1,19, %U A195827 16,13,7,2,20,17,14,8,3,21,18,15,9,4,22,19,16,10,5 %N A195827 Triangle read by rows with T(n,k) = n - A085787(k), n>=1, k>=1, if (n - A085787(k))>=0. %C A195827 Also triangle read by rows in which column k lists the nonnegative integers A001477 starting at the row A085787(k). %C A195827 This sequence is related to the generalized heptagonal numbers A085787, A195837 and A036820 in the same way as A195310 is related to the generalized pentagonal numbers A001318, A175003 and A000041. See comments in A195825. %e A195827 Written as a triangle: %e A195827 . 0; %e A195827 . 1; %e A195827 . 2; %e A195827 . 3, 0; %e A195827 . 4, 1; %e A195827 . 5, 2; %e A195827 . 6, 3, 0; %e A195827 . 7, 4, 1; %e A195827 . 8, 5, 2; %e A195827 . 9, 6, 3; %e A195827 . 10, 7, 4; %e A195827 . 11, 8, 5; %e A195827 . 12, 9, 6, 0; %e A195827 . 13, 10, 7, 1; %e A195827 . 14, 11, 8, 2; %Y A195827 Cf. A036820, A085787, A195310, A195825, A195826, A195828, A195829, A195830, A195831, A195832, A195833, A195837. %K A195827 nonn,tabf %O A195827 1,3 %A A195827 _Omar E. Pol_, Sep 24 2011