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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.

A322785 Number of uniform multiset partitions of uniform multisets of size n whose union is an initial interval of positive integers.

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%I A322785 #17 Feb 03 2022 16:45:59
%S A322785 1,1,4,4,12,4,48,4,183,297,1186,4,33950,4,139527,1529608,4726356,4,
%T A322785 229255536,4,3705777010,36279746314,13764663019,4,14096735197959,
%U A322785 5194673049514,7907992957755,2977586461058927,13426396910491001,4,1350012288268171854,4,59487352224070807287
%N A322785 Number of uniform multiset partitions of uniform multisets of size n whose union is an initial interval of positive integers.
%C A322785 A multiset is uniform if all multiplicities are equal. A multiset partition is uniform if all parts have the same size.
%H A322785 Andrew Howroyd, <a href="/A322785/b322785.txt">Table of n, a(n) for n = 0..100</a>
%F A322785 a(n) = 4 <=> n in { A000040 }. - _Alois P. Heinz_, Feb 03 2022
%e A322785 The a(1) = 1 though a(6) = 48 multiset partitions:
%e A322785   {1}  {11}    {111}      {1111}        {11111}          {111111}
%e A322785        {12}    {123}      {1122}        {12345}          {111222}
%e A322785        {1}{1}  {1}{1}{1}  {1234}        {1}{1}{1}{1}{1}  {112233}
%e A322785        {1}{2}  {1}{2}{3}  {11}{11}      {1}{2}{3}{4}{5}  {123456}
%e A322785                           {11}{22}                       {111}{111}
%e A322785                           {12}{12}                       {111}{222}
%e A322785                           {12}{34}                       {112}{122}
%e A322785                           {13}{24}                       {112}{233}
%e A322785                           {14}{23}                       {113}{223}
%e A322785                           {1}{1}{1}{1}                   {122}{133}
%e A322785                           {1}{1}{2}{2}                   {123}{123}
%e A322785                           {1}{2}{3}{4}                   {123}{456}
%e A322785                                                          {124}{356}
%e A322785                                                          {125}{346}
%e A322785                                                          {126}{345}
%e A322785                                                          {134}{256}
%e A322785                                                          {135}{246}
%e A322785                                                          {136}{245}
%e A322785                                                          {145}{236}
%e A322785                                                          {146}{235}
%e A322785                                                          {156}{234}
%e A322785                                                          {11}{11}{11}
%e A322785                                                          {11}{12}{22}
%e A322785                                                          {11}{22}{33}
%e A322785                                                          {11}{23}{23}
%e A322785                                                          {12}{12}{12}
%e A322785                                                          {12}{12}{33}
%e A322785                                                          {12}{13}{23}
%e A322785                                                          {12}{34}{56}
%e A322785                                                          {12}{35}{46}
%e A322785                                                          {12}{36}{45}
%e A322785                                                          {13}{13}{22}
%e A322785                                                          {13}{24}{56}
%e A322785                                                          {13}{25}{46}
%e A322785                                                          {13}{26}{45}
%e A322785                                                          {14}{23}{56}
%e A322785                                                          {14}{25}{36}
%e A322785                                                          {14}{26}{35}
%e A322785                                                          {15}{23}{46}
%e A322785                                                          {15}{24}{36}
%e A322785                                                          {15}{26}{34}
%e A322785                                                          {16}{23}{45}
%e A322785                                                          {16}{24}{35}
%e A322785                                                          {16}{25}{34}
%e A322785                                                          {1}{1}{1}{1}{1}{1}
%e A322785                                                          {1}{1}{1}{2}{2}{2}
%e A322785                                                          {1}{1}{2}{2}{3}{3}
%e A322785                                                          {1}{2}{3}{4}{5}{6}
%t A322785 sps[{}]:={{}};sps[set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,___}];
%t A322785 mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
%t A322785 Table[Sum[Length[Select[mps[m],SameQ@@Length/@#&]],{m,Table[Join@@Table[Range[n/d],{d}],{d,Divisors[n]}]}],{n,8}]
%Y A322785 Row sums of A322788.
%Y A322785 Cf. A000040, A038041, A072774, A100778, A299353, A306017, A306018, A306021, A317583, A317584, A319056, A319189, A321721, A322705, A322784, A322788.
%K A322785 nonn
%O A322785 0,3
%A A322785 _Gus Wiseman_, Dec 26 2018
%E A322785 More terms from _Alois P. Heinz_, Jan 30 2019
%E A322785 Terms a(14) and beyond from _Andrew Howroyd_, Feb 03 2022