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 A365543 #14 Apr 05 2025 23:17:53 %S A365543 1,1,1,2,1,2,3,2,2,3,5,3,3,3,5,7,5,5,5,5,7,11,7,8,6,8,7,11,15,11,11, %T A365543 11,11,11,11,15,22,15,17,15,14,15,17,15,22,30,22,23,23,22,22,23,23,22, %U A365543 30,42,30,33,30,33,25,33,30,33,30,42 %N A365543 Triangle read by rows where T(n,k) is the number of integer partitions of n with a submultiset summing to k. %C A365543 Rows are palindromic. %H A365543 Robert Price, <a href="/A365543/b365543.txt">Table of n, a(n) for n = 0..324</a> %e A365543 Triangle begins: %e A365543 1 %e A365543 1 1 %e A365543 2 1 2 %e A365543 3 2 2 3 %e A365543 5 3 3 3 5 %e A365543 7 5 5 5 5 7 %e A365543 11 7 8 6 8 7 11 %e A365543 15 11 11 11 11 11 11 15 %e A365543 22 15 17 15 14 15 17 15 22 %e A365543 30 22 23 23 22 22 23 23 22 30 %e A365543 42 30 33 30 33 25 33 30 33 30 42 %e A365543 56 42 45 44 44 43 43 44 44 45 42 56 %e A365543 77 56 62 58 62 56 53 56 62 58 62 56 77 %e A365543 Row n = 6 counts the following partitions: %e A365543 (6) (51) (42) (33) (42) (51) (6) %e A365543 (51) (411) (411) (321) (411) (411) (51) %e A365543 (42) (321) (321) (3111) (321) (321) (42) %e A365543 (411) (3111) (3111) (2211) (3111) (3111) (411) %e A365543 (33) (2211) (222) (21111) (222) (2211) (33) %e A365543 (321) (21111) (2211) (111111) (2211) (21111) (321) %e A365543 (3111) (111111) (21111) (21111) (111111) (3111) %e A365543 (222) (111111) (111111) (222) %e A365543 (2211) (2211) %e A365543 (21111) (21111) %e A365543 (111111) (111111) %t A365543 Table[Length[Select[IntegerPartitions[n],MemberQ[Total/@Subsets[#],k]&]],{n,0,15},{k,0,n}] %Y A365543 Columns k = 0 and k = n are A000041. %Y A365543 Central column n = 2k is A002219. %Y A365543 The complement is counted by A046663, strict A365663. %Y A365543 Row sums are A304792. %Y A365543 For subsets instead of partitions we have A365381. %Y A365543 The strict case is A365661. %Y A365543 A000009 counts subsets summing to n. %Y A365543 A000124 counts distinct possible sums of subsets of {1..n}. %Y A365543 A364272 counts sum-full strict partitions, sum-free A364349. %Y A365543 Cf. A088809, A093971, A122768, A108917, A299701, A364911, A365541, A365658. %K A365543 nonn,tabl %O A365543 0,4 %A A365543 _Gus Wiseman_, Sep 16 2023