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 A321737 #12 Aug 29 2023 13:12:43 %S A321737 1,1,3,9,37,152,780,3965,23460,141471,944217,6445643,48075092, %T A321737 364921557,2974423953,24847873439,219611194148,1987556951714, %U A321737 18930298888792,184244039718755,1874490999743203,19510832177784098,210941659716920257,2331530519337226199,26692555830628617358 %N A321737 Number of ways to partition the Young diagram of an integer partition of n into vertical sections. %C A321737 A vertical section is a partial Young diagram with at most one square in each row. For example, a partition (shown as a coloring by positive integers) into vertical sections of the Young diagram of (322) is: %C A321737 1 2 3 %C A321737 1 2 %C A321737 2 3 %e A321737 The a(4) = 37 partitions into vertical sections of integer partitions of 4: %e A321737 1 2 3 4 %e A321737 . %e A321737 1 2 3 1 2 3 1 2 3 1 2 3 %e A321737 4 3 2 1 %e A321737 . %e A321737 1 2 1 2 1 2 1 2 1 2 1 2 1 2 %e A321737 3 4 2 3 3 2 1 3 1 2 3 1 2 1 %e A321737 . %e A321737 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 1 2 %e A321737 3 3 2 3 2 1 1 3 2 1 %e A321737 4 3 3 2 2 3 2 1 1 1 %e A321737 . %e A321737 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 %e A321737 2 2 2 2 2 1 1 2 2 2 2 1 1 2 1 %e A321737 3 3 2 3 2 2 2 1 1 3 2 1 2 1 1 %e A321737 4 3 3 2 2 3 2 3 2 1 1 2 1 1 1 %t A321737 spsu[_,{}]:={{}};spsu[foo_,set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@spsu[Select[foo,Complement[#,Complement[set,s]]=={}&],Complement[set,s]]]/@Cases[foo,{i,___}]; %t A321737 ptnpos[y_]:=Position[Table[1,{#}]&/@y,1]; %t A321737 ptnverts[y_]:=Select[Rest[Subsets[ptnpos[y]]],UnsameQ@@First/@#&]; %t A321737 Table[Sum[Length[spsu[ptnverts[y],ptnpos[y]]],{y,IntegerPartitions[n]}],{n,6}] %Y A321737 Cf. A000110, A000258, A008277, A046682, A122111, A318396, A321728, A321729, A321730, A321731, A321738, A321854. %K A321737 nonn %O A321737 0,3 %A A321737 _Gus Wiseman_, Nov 19 2018 %E A321737 a(11)-a(24) from _Ludovic Schwob_, Aug 28 2023