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 A211025 #18 Dec 01 2013 13:36:34 %S A211025 1,1,3,1,2,5,1,2,3,5,7,11,1,2,3,4,5,7,10,15,1,2,3,4,5,6,7,9,11,13,15, %T A211025 19,22,25,31,1,2,3,4,5,6,7,8,9,10,11,13,15,18,20,25,28,32,39,1,2,3,4, %U A211025 5,6,7,8,9,10,11,12,13,14,15,17,19,21,23,25,27 %N A211025 Triangle read by rows: T(n,k) = total sum of parts in the last section of the set of partitions of n after k-th stage. %C A211025 Also triangle read by rows in which row n lists the partial sums of row n of triangle A135010. %C A211025 This triangle shows the growth of the last sections of the partitions of n step by step. At stage k one part of size A135010(n,k) is added to the structure of the n-th shell. %e A211025 For row n = 5 of triangle we have: %e A211025 ------------------------------------- %e A211025 Column Zone The 5th Total sum %e A211025 k shell of parts %e A211025 ------------------------------------- %e A211025 8 <> 7 (5) 15 %e A211025 7 <> 6 (3... 10 %e A211025 6 = 6 ...2) 7 %e A211025 5 = 5 (1) 5 %e A211025 4 = 4 (1) 4 %e A211025 3 = 3 (1) 3 %e A211025 2 = 2 (1) 2 %e A211025 1 = 1 (1) 1 %e A211025 . %e A211025 Triangle begins: %e A211025 1; %e A211025 1,3; %e A211025 1,2,5; %e A211025 1,2,3,5,7,11; %e A211025 1,2,3,4,5,7,10,15; %e A211025 1,2,3,4,5,6,7,9,11,13,15,19,22,25,31; %e A211025 1,2,3,4,5,6,7,8,9,10,11,13,15,18,20,25,28,32,39; %Y A211025 Row n has length A138137(n). Right border gives A138879. %Y A211025 Cf. A135010, A182703, A206437, A211030. %K A211025 nonn,tabf %O A211025 1,3 %A A211025 _Omar E. Pol_, Apr 25 2012