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 A371790 #10 Apr 01 2025 07:15:38
%S A371790 1,2,3,6,11,21,40,77,144,279,517,1004,1882,3635,6912,13223,25163,
%T A371790 48927,93770,182765,355226,688259,1333939,2617253,5109865,10012410,
%U A371790 19624287,38356485,74987607,147268359
%N A371790 Number of non-quanimous subsets of {1..n} containing n, meaning there is only one set partition with equal block-sums.
%e A371790 The set s = {3,4,6,8,9} has set partitions {{3,4,6,8,9}} and {{3,4,8},{6,9}} with equal block-sums, so s is not counted under a(9).
%e A371790 The a(1) = 1 through a(5) = 11 subsets:
%e A371790 {1} {2} {3} {4} {5}
%e A371790 {1,2} {1,3} {1,4} {1,5}
%e A371790 {2,3} {2,4} {2,5}
%e A371790 {3,4} {3,5}
%e A371790 {1,2,4} {4,5}
%e A371790 {2,3,4} {1,2,5}
%e A371790 {1,3,5}
%e A371790 {2,4,5}
%e A371790 {3,4,5}
%e A371790 {1,2,3,5}
%e A371790 {1,3,4,5}
%t A371790 sps[{}]:={{}};sps[set:{i_,___}]:=Join@@Function[s,Prepend[#,s]& /@ sps[Complement[set,s]]]/@Cases[Subsets[set],{i,___}];
%t A371790 Table[Length[Select[Subsets[Range[n]], MemberQ[#,n]&&Length[Select[sps[#],SameQ@@Total/@#&]]==1&]],{n,10}]
%Y A371790 First differences of A371789, complement counted by A371796.
%Y A371790 The "bi-" version is A371793, complement A232466.
%Y A371790 The complement is counted by A371797.
%Y A371790 A371736 counts non-quanimous strict partitions.
%Y A371790 A371737 counts quanimous strict partitions.
%Y A371790 A371783 counts k-quanimous partitions.
%Y A371790 A371791 counts biquanimous subsets, complement A371792.
%Y A371790 Cf. A002219, A035470, A038041, A275972, A316402, A321451, A321452.
%K A371790 nonn,more
%O A371790 1,2
%A A371790 _Gus Wiseman_, Apr 17 2024
%E A371790 a(11)-a(30) from _Martin Fuller_, Apr 01 2025