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 A140581 #4 Apr 05 2012 17:24:06 %S A140581 1,1,1,2,0,1,0,1,0,1,4,0,0,0,1,-3,2,1,0,0,1,6,0,0,0,0,0,1,0,0,0,1,0,0, %T A140581 0,1,0,0,2,0,0,0,0,0,1,-5,4,0,0,1,0,0,0,0,1,10,0,0,0,0,0,0,0,0,0,1,0, %U A140581 -3,0,20,1,0,0,0,0,0,1,12,0,0,0,0,0,0,0,0,0,0,0,1,-7,6,0,0,0,0,1,0,0,0,0,0,0,1 %N A140581 Triangle read by rows, A054525 * A140256. %C A140581 Row sums = A014963: (1, 2, 3, 2, 5, 1, 7, 2, 3, 1, 11, 1, 13, 1,...). %F A140581 Mobius transform of triangle A140256 = A054525 * A140256; as infinite lower triangular matrices. %e A140581 First few rows of the triangle are: %e A140581 1; %e A140581 1, 1; %e A140581 2, 0, 1; %e A140581 0, 1, 0, 1; %e A140581 4, 0, 0, 0, 1; %e A140581 -3, 2, 1, 0, 0, 1; %e A140581 6, 0, 0, 0, 0, 0, 1; %e A140581 0, 0, 0, 1, 0, 0, 0, 1; %e A140581 0, 0, 2, 0, 0, 0, 0, 0, 1; %e A140581 ... %Y A140581 Cf. A140256, A054525. %K A140581 tabl,sign %O A140581 1,4 %A A140581 _Gary W. Adamson_ and _Mats Granvik_, May 17 2008