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 A209666 #16 Nov 17 2018 15:25:41 %S A209666 1,2,7,3,18,55,5,50,216,631,7,118,729,2780,8001,11,301,2621,12954, %T A209666 45865,130453,15,684,8535,55196,241870,820554,2323483,22,1621,28689, %U A209666 241634,1307055,5280204,17353028,48916087,30,3620,91749,1012196,6783210,32711022,124991685,401709720,1129559068 %N A209666 T(n,k) = count of degree k monomials in the complete homogeneous symmetric polynomials h(mu,k) summed over all partitions mu of n. %H A209666 Alois P. Heinz, <a href="/A209666/b209666.txt">Rows n = 1..141, flattened</a> %H A209666 Wikipedia, <a href="http://en.wikipedia.org/wiki/Symmetric_polynomials">Symmetric Polynomials</a> %e A209666 Table starts as: %e A209666 1; %e A209666 2, 7; %e A209666 3, 18, 55; %e A209666 5, 50, 216, 631; %e A209666 7, 118, 729, 2780, 8001; %p A209666 b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0, %p A209666 add(b(n-i*j, i-1, k)*binomial(i+k-1, k-1)^j, j=0..n/i))) %p A209666 end: %p A209666 T:= (n, k)-> b(n$2, k): %p A209666 seq(seq(T(n, k), k=1..n), n=1..10); # _Alois P. Heinz_, Mar 04 2016 %t A209666 h[n_, v_] := Tr@ Apply[Times, Table[Subscript[x, j], {j, v}]^# & /@ Compositions[n, v], {1}]; h[par_?PartitionQ, v_] := Times @@ (h[#, v] & /@ par); Table[Tr[(h[#, k] & /@ Partitions[l]) /. Subscript[x, _] -> 1], {l, 10}, {k, l}] %Y A209666 Main diagonal is A209668; row sums are A209667. %K A209666 nonn,tabl %O A209666 1,2 %A A209666 _Wouter Meeussen_, Mar 11 2012