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 A145972 #5 Jun 02 2025 00:41:55 %S A145972 1,1,1,2,1,1,2,3,1,1,4,3,4,1,1,4,8,4,5,1,1,9,8,13,5,6,1,1,9,22,13,19, %T A145972 6,7,1,1,23,22,41,19,26,7,8,1,1,23,64,41,67,26,34,8,9,1,1,65,64,131, %U A145972 67,101,34,43,9,10,1,1 %N A145972 Triangle read by rows, A000012 * A053121. %C A145972 Row sums = A036256: (1, 2, 4, 7, 13, 23, 43,...). %F A145972 Triangle read by rows, A000012 * A053121, = partial sums of column terms of triangle A053121. %e A145972 A053121 starts: %e A145972 1; %e A145972 0, 1; %e A145972 1, 0, 1; %e A145972 0, 2, 0, 1; %e A145972 ... %e A145972 Taking partial sums from the top, we get A145972: %e A145972 1; %e A145972 1, 1; %e A145972 2, 1, 1; %e A145972 2, 3, 1, 1; %e A145972 4, 3, 4, 1, 1; %e A145972 4, 8, 4, 5, 1, 1; %e A145972 9, 8, 13, 5, 6, 1, 1; %e A145972 9, 22, 13, 19, 6, 7, 1, 1; %e A145972 23, 22, 41, 19, 26, 7, 8, 1, 1; %e A145972 23, 64, 41, 67, 26, 34, 8, 9, 1, 1; %e A145972 ... %Y A145972 Cf. A036256, A053121 %K A145972 nonn,tabl %O A145972 0,4 %A A145972 _Gary W. Adamson_ & _Roger L. Bagula_, Oct 25 2008