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 A152903 #8 Jun 02 2025 01:15:37 %S A152903 1,-1,3,-1,-3,7,0,-3,-7,14,-1,0,-7,-14,-1,0,-7,-14,1,-3,0,-14,-27,49, %T A152903 -1,3,-7,0,-27,-49,88,0,-3,7,-14,0,-49,-88,155,0,0,-7,14,-27,0,-88, %U A152903 -155,272,1,0,0,-14,27,-49,0,-155,-272,472 %N A152903 Convolution triangle: A152901 * (A152902 * 0^(n-k)). %C A152903 Row sums = n, equivalent to the statement that A008683 convolved with A152902 = A000027, the natural numbers. Right border = A152902, left border = A008683. %F A152903 Triangle read by rows, A152901 * (A152902 * 0^(n-k); where triangle A152901 = a mu(n) "decrescendo" triangle with mu(n), A008683 in every column. (A152902 * 0^(n-k)) = a matrix with A152902 as the main diagonal and the rest zeros. %e A152903 First few rows of the triangle = %e A152903 1; %e A152903 -1, 3; %e A152903 -1, -3, 7; %e A152903 0, -3, -7, 14; %e A152903 -1, 0, -7, -14, 27; %e A152903 1, -3, 0, -14, -27, 49; %e A152903 -1, 3, -7, 0, -27, -49, 88; %e A152903 0, -3, 7, -14, 0, -49, -88, 155; %e A152903 0, 0, -7, 14, -27, 0, -88, -155, 272; %e A152903 1, 0, 0, -14, 27, -49, 0, -155, -272, 472; %e A152903 -1, 3, 0, 0, -27, 49, -88, 0, -272, -472, 819; %e A152903 ... %Y A152903 Cf. A152901, A152902, A000027, A008683. %K A152903 tabl,sign %O A152903 1,3 %A A152903 _Gary W. Adamson_, Dec 14 2008