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 A210961 #15 May 23 2012 17:36:13 %S A210961 1,1,2,1,1,2,1,3,1,1,1,2,1,5,1,1,4,3,1,1,1,2,1,5,1,1,7,3,1,1,5,3,2,1, %T A210961 1,1,2,1,5,1,1,9,3,1,1,12,5,2,1,1,6,6,4,2,1,1,1,2,1,5,1,1,9,3,1,1,15, %U A210961 5,2,1,1,15,8,4,2,1,1,7,6,5,3,2,1,1 %N A210961 Tetrahedron T(j,n,k) in which the slice j is a finite triangle read by rows T(n,k) which lists the sums of the columns of the shell model of partitions with n shells mentioned in A210970. %e A210961 -------------------------------------------------------- %e A210961 Illustration of first five A210952 %e A210961 slices of the tetrahedron Row sum %e A210961 -------------------------------------------------------- %e A210961 . 1, 1 %e A210961 . 1, 1 %e A210961 . 2, 1, 3 %e A210961 . 1, 1 %e A210961 . 2, 1, 3 %e A210961 . 3, 1, 1, 5 %e A210961 . 1, 1 %e A210961 . 2, 1, 3 %e A210961 . 5, 1, 1, 7 %e A210961 . 4, 3, 1, 1, 9 %e A210961 . 1, 1 %e A210961 . 2, 1, 3 %e A210961 . 5, 1, 1, 7 %e A210961 . 7, 3, 1, 1, 12 %e A210961 . 5, 3, 2, 1, 1, 12 %e A210961 -------------------------------------------------------- %e A210961 . 1, 3, 1, 6, 2, 1,12, 5, 2, 1,20, 8, 4, 2, 1, %e A210961 . %e A210961 Column sums give A181187. %e A210961 Also, written as a triangle read by rows in which each row is a flattened triangle, begins: %e A210961 1; %e A210961 1,2,1; %e A210961 1,2,1,3,1,1; %e A210961 1,2,1,5,1,1,4,3,1,1; %e A210961 1,2,1,5,1,1,7,3,1,1,5,3,2,1,1; %e A210961 1,2,1,5,1,1,9,3,1,1,12,5,2,1,1,6,6,4,2,1,1; %e A210961 1,2,1,5,1,1,9,3,1,1,15,5,2,1,1,15,8,4,2,1,1,7,6,5,3,2,1,1; %e A210961 In which row sums give A066186. %Y A210961 Cf. A066186, A135010, A138121, A181187, A210952, A210960, A210970. %K A210961 nonn,tabf %O A210961 1,3 %A A210961 _Omar E. Pol_, Apr 22 2012