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 A132778 #9 Jun 03 2023 17:31:51 %S A132778 1,3,2,5,5,3,7,7,7,4,9,9,9,9,5,11,11,11,11,11,6,13,13,13,13,13,13,7, %T A132778 15,15,15,15,15,15,15,8,17,17,17,17,17,17,17,17,9,19,19,19,19,19,19, %U A132778 19,19,19,10,21,21,21,21,21,21,21,21,21,21,11,23,23,23,23,23,23,23,23,23,23,23,12 %N A132778 Triangle read by rows, n-1 terms of (2n - 1) followed by n. %C A132778 Row sums = A001844: (1, 5, 13, 25, 41, 61, ...). %F A132778 A007318^(-1) * [A003506 * A000012], as infinite lower triangular matrices. %e A132778 First few rows of the triangle: %e A132778 1; %e A132778 3, 2; %e A132778 5, 5, 3; %e A132778 7, 7, 7, 4; %e A132778 9, 9, 9, 9, 5; %e A132778 ... %Y A132778 Cf. A001844, A003506, A007318. %K A132778 nonn,tabl %O A132778 1,2 %A A132778 _Gary W. Adamson_, Aug 29 2007 %E A132778 Spurious extra term after a(44) deleted and more terms from _Georg Fischer_, Jun 02 2023