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 A225598 #18 Mar 13 2015 22:58:17 %S A225598 1,1,3,1,3,5,1,5,5,9,1,5,8,9,12,1,7,11,15,12,20,1,7,14,19,19,20,25,1, %T A225598 9,17,29,24,33,25,38,1,9,23,33,36,42,39,38,49,1,11,26,47,46,61,49,61, %U A225598 49,69,1,11,32,55,63,76,70,76,76,69,87,1,13,38,73,78,110,87,111,95,108,87,123 %N A225598 Triangle read by rows: T(n,k) = sum of all parts of all regions of the set of partitions of n whose largest part is k. %C A225598 For the definition of region see A206437. %C A225598 T(n,k) is also the sum of all parts that end in the k-th column of the diagram of regions of the set of partitions of n (see Example section). %e A225598 For n = 5 and k = 3 the set of partitions of 5 contains two regions whose largest part is 3, they are third region which contains three parts [3, 1, 1] and the sixth region which contains only one part [3]. Therefore the sum of all parts is 3 + 1 + 1 + 3 = 8, so T(5,3) = 8. %e A225598 . %e A225598 . Diagram Illustration of parts ending in column k: %e A225598 . for n=5 k=1 k=2 k=3 k=4 k=5 %e A225598 . _ _ _ _ _ _ _ _ _ _ %e A225598 . |_ _ _ | _ _ _ |_ _ _ _ _| %e A225598 . |_ _ _|_ | |_ _ _| _ _ _ _ |_ _| %e A225598 . |_ _ | | _ _ |_ _ _ _| |_| %e A225598 . |_ _|_ | | |_ _| _ _ _ |_ _| |_| %e A225598 . |_ _ | | | _ _ |_ _ _| |_| |_| %e A225598 . |_ | | | | _ |_ _| |_| |_| |_| %e A225598 . |_|_|_|_|_| |_| |_| |_| |_| |_| %e A225598 . %e A225598 k = 1 2 3 4 5 %e A225598 . %e A225598 The 5th row lists: 1 5 8 9 12 %e A225598 . %e A225598 Triangle begins: %e A225598 1; %e A225598 1, 3; %e A225598 1, 3, 5; %e A225598 1, 5, 5, 9; %e A225598 1, 5, 8, 9, 12; %e A225598 1, 7, 11, 15, 12, 20; %e A225598 1, 7, 14, 19, 19, 20, 25; %e A225598 1, 9, 17, 29, 24, 33, 25, 38; %e A225598 1, 9, 23, 33, 36, 42, 39, 38, 49; %e A225598 1, 11, 26, 47, 46, 61, 49, 61, 49, 69; %e A225598 1, 11, 32, 55, 63, 76, 70, 76, 76, 69, 87; %e A225598 1, 13, 38, 73, 78, 110, 87, 111, 95, 108, 87, 123; %Y A225598 Column 1 is A000012. Column 2 are the numbers >= 3 of A109613. Row sums give A066186. Right border gives A046746. Second right border gives A046746. %Y A225598 Cf. A000041, A066186, A135010, A141285, A186114, A186412, A187219, A194446, A206437, A207779, A211978, A225597, A225600, A225610. %K A225598 nonn,tabf %O A225598 1,3 %A A225598 _Omar E. Pol_, Aug 02 2013