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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.

A371954 Triangle read by rows where T(n,k) is the number of integer partitions of n that can be partitioned into k multisets with equal sums (k-quanimous).

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%I A371954 #8 Apr 20 2024 10:49:28
%S A371954 1,0,1,0,2,1,0,3,0,1,0,5,3,0,1,0,7,0,0,0,1,0,11,6,4,0,0,1,0,15,0,0,0,
%T A371954 0,0,1,0,22,14,0,5,0,0,0,1,0,30,0,10,0,0,0,0,0,1,0,42,25,0,0,6,0,0,0,
%U A371954 0,1,0,56,0,0,0,0,0,0,0,0,0,1,0,77,53,30,15,0,7,0,0,0,0,0,1
%N A371954 Triangle read by rows where T(n,k) is the number of integer partitions of n that can be partitioned into k multisets with equal sums (k-quanimous).
%C A371954 A finite multiset of numbers is defined to be k-quanimous iff it can be partitioned into k multisets with equal sums.
%e A371954 Triangle begins:
%e A371954   1
%e A371954   0  1
%e A371954   0  2  1
%e A371954   0  3  0  1
%e A371954   0  5  3  0  1
%e A371954   0  7  0  0  0  1
%e A371954   0 11  6  4  0  0  1
%e A371954   0 15  0  0  0  0  0  1
%e A371954   0 22 14  0  5  0  0  0  1
%e A371954   0 30  0 10  0  0  0  0  0  1
%e A371954   0 42 25  0  0  6  0  0  0  0  1
%e A371954   0 56  0  0  0  0  0  0  0  0  0  1
%e A371954   0 77 53 30 15  0  7  0  0  0  0  0  1
%e A371954 Row n = 6 counts the following partitions:
%e A371954   .  (6)       (33)      (222)     .  .  (111111)
%e A371954      (51)      (321)     (2211)
%e A371954      (42)      (3111)    (21111)
%e A371954      (411)     (2211)    (111111)
%e A371954      (33)      (21111)
%e A371954      (321)     (111111)
%e A371954      (3111)
%e A371954      (222)
%e A371954      (2211)
%e A371954      (21111)
%e A371954      (111111)
%t A371954 hwt[n_]:=Total[Cases[FactorInteger[n],{p_,k_}:>PrimePi[p]*k]];
%t A371954 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&, Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A371954 Table[Length[Select[IntegerPartitions[n], Select[facs[Times@@Prime/@#], Length[#]==k&&SameQ@@hwt/@#&]!={}&]],{n,0,10},{k,0,n}]
%Y A371954 Row n has A000005(n) positive entries.
%Y A371954 Column k = 1 is A000041.
%Y A371954 Column k = 2 is A002219 (aerated), ranks A357976.
%Y A371954 Column k = 3 is A002220 (aerated), ranks A371955.
%Y A371954 Removing all zeros gives A371783.
%Y A371954 Row sums are A372121.
%Y A371954 A321451 counts non-quanimous partitions, ranks A321453.
%Y A371954 A321452 counts quanimous partitions, ranks A321454.
%Y A371954 A371789 counts non-quanimous sets, complement A371796.
%Y A371954 Cf. A002221, A002222, A006827, A035470, A064914, A237258, A321142, A321455, A365543, A371795.
%K A371954 nonn,tabl
%O A371954 0,5
%A A371954 _Gus Wiseman_, Apr 20 2024