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 A195830 #9 Mar 30 2012 17:34:07 %S A195830 0,1,2,3,4,5,6,0,7,1,8,2,9,3,0,10,4,1,11,5,2,12,6,3,13,7,4,14,8,5,15, %T A195830 9,6,16,10,7,17,11,8,18,12,9,19,13,10,20,14,11,21,15,12,0,22,16,13,1, %U A195830 23,17,14,2,24,18,15,3,25,19,16,4,26,20,17,5,0 %N A195830 Triangle read by rows with T(n,k) = n - A074377(k), n>=1, k>=1, if (n - A074377(k))>=0. %C A195830 Also triangle read by rows in which column k lists the nonnegative integers A001477 starting at the row A074377(k). %C A195830 This sequence is related to the generalized decagonal numbers A074377, A195840 and A195850 in the same way as A195310 is related to the generalized pentagonal numbers A001318, A175003 and A000041. See comments in A195825. %e A195830 Written as a triangle: %e A195830 . 0; %e A195830 . 1; %e A195830 . 2; %e A195830 . 3; %e A195830 . 4; %e A195830 . 5; %e A195830 . 6, 0; %e A195830 . 7, 1; %e A195830 . 8, 2; %e A195830 . 9, 3, 0; %e A195830 . 10, 4, 1; %e A195830 . 11, 5, 2; %e A195830 . 12, 6, 3; %e A195830 . 13, 7, 4; %e A195830 . 14, 8, 5; %e A195830 . 15, 9, 6; %e A195830 . 16, 10, 7; %e A195830 . 17, 11, 8; %e A195830 . 18, 12, 9; %e A195830 . 19, 13, 10; %e A195830 . 20, 14, 11; %e A195830 . 21, 15, 12, 0; %e A195830 . 22, 16, 13, 1; %e A195830 . 23, 17, 14, 2; %Y A195830 Cf. A074377, A195310, A195825, A195826, A195827, A195828, A195829, A195831, A195832, A195833, A195840, A195850. %K A195830 nonn,tabf %O A195830 1,3 %A A195830 _Omar E. Pol_, Sep 24 2011