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 A195836 #18 Mar 30 2012 17:34:07 %S A195836 1,1,1,1,2,1,3,1,4,2,-1,5,3,-1,7,4,-1,10,5,-2,13,7,-3,-1,16,10,-4,-1, %T A195836 21,13,-5,-1,28,16,-7,-2,35,21,-10,-3,43,28,-13,-4,1,55,35,-16,-5,1, %U A195836 70,43,-21,-7,1,86,55,-28,-10,2,105,70,-35,-13,3,130,86,-43,-16,4 %N A195836 Triangle read by rows which arises from A195826 in the same way as A175003 arises from A195310. Column k starts at row A000217(k). %C A195836 The sum of terms of row n is equal to the leftmost term of row n+1. It appears that this sequence is related to the generalized hexagonal numbers (A000217), A195826 and A006950 in the same way as A175003 is related to the generalized pentagonal numbers A001318, A195310 and A000041. It appears that row sums give A006950. See comments in A195825. %e A195836 Written as a triangle: %e A195836 . 1, %e A195836 . 1, %e A195836 . 1, 1, %e A195836 . 2, 1, %e A195836 . 3, 1, %e A195836 . 4, 2, -1, %e A195836 . 5, 3, -1, %e A195836 . 7, 4, -1, %e A195836 . 10, 5, -2, %e A195836 . 13, 7, -3, -1, %e A195836 . 16, 10, -4, -1, %e A195836 . 21, 13, -5, -1, %e A195836 . 28, 16, -7, -2, %e A195836 . 35, 21, -10, -3, %e A195836 . 43, 28, -13, -4, 1, %e A195836 . 55, 35, -16, -5, 1, %e A195836 . 70, 43, -21, -7, 1, %e A195836 . 86, 55, -28, -10, 2, %Y A195836 Cf. A000217, A006950, A175003, A195825, A195826, A195837, A195838, A195939, A195840, A195841, A195842, A195843. %K A195836 sign,tabf %O A195836 1,5 %A A195836 _Omar E. Pol_, Sep 24 2011