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 A210945 #27 May 21 2012 15:35:52 %S A210945 1,2,3,5,1,7,1,11,3,1,15,3,1,22,6,3,1,30,7,4,1,42,11,7,3,1,56,13,9,4, %T A210945 1,77,20,15,8,3,1,101,23,18,10,4,1,135,33,27,17,8,3,1,176,40,34,22,11, %U A210945 4,1,231,54,47,33,18,8,3,1,297,65,58,42,24,11,4,1 %N A210945 Triangle read by rows: T(n,k) = number of parts in the k-th column of the mirror of the last shell of the partitions of n. %C A210945 For another version see A207379. %H A210945 Alois P. Heinz, <a href="/A210945/b210945.txt">Rows n = 1..70</a> %e A210945 For n = 7 the illustration shows two arrangements of the last shell of the partitions of 7: %e A210945 . %e A210945 . (7) (7) %e A210945 . (4+3) (3+4) %e A210945 . (5+2) (2+5) %e A210945 . (3+2+2) (2+2+3) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . (1) (1) %e A210945 . -------- %e A210945 . 15,3,1 %e A210945 . %e A210945 We can see that in the right hand picture (the mirror) the number of part for columns 1..3 are 15, 3, 1 therefore row 7 lists 15, 3, 1. %e A210945 Written as a triangle begins: %e A210945 1; %e A210945 2; %e A210945 3; %e A210945 5, 1; %e A210945 7, 1; %e A210945 11, 3, 1; %e A210945 15, 3, 1; %e A210945 22, 6, 3, 1; %e A210945 30, 7, 4, 1; %e A210945 42, 11, 7, 3, 1; %e A210945 56, 13, 9, 4, 1; %e A210945 77, 20, 15, 8, 3, 1; %e A210945 101, 23, 18, 10, 4, 1; %e A210945 135, 33, 27, 17, 8, 3, 1; %e A210945 176, 40, 34, 22, 11, 4, 1; %e A210945 231, 54, 47, 33, 18, 8, 3, 1; %e A210945 297, 65, 58, 42, 24, 11, 4, 1; %Y A210945 Column 1 is A000041,n >= 1. Column 2 is A083751. Column 3 is A119907. Row sums give A138137. %Y A210945 Cf. A135010, A138121, A182717, A207379. %K A210945 nonn,tabf %O A210945 1,2 %A A210945 _Omar E. Pol_, Apr 21 2012 %E A210945 More terms from _Alois P. Heinz_, May 07 2012