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A367582 Triangle read by rows where T(n,k) is the number of integer partitions of n whose multiset multiplicity kernel (in which each multiplicity becomes the least element of that multiplicity), sums to k.

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%I A367582 #6 Nov 29 2023 06:56:12
%S A367582 1,0,1,0,1,1,0,1,1,1,0,1,2,1,1,0,1,1,2,2,1,0,1,3,3,2,1,1,0,1,1,4,3,3,
%T A367582 2,1,0,1,3,5,4,4,3,1,1,0,1,2,6,4,8,3,3,2,1,0,1,3,7,9,6,7,4,3,1,1,0,1,
%U A367582 1,8,7,11,9,9,4,3,2,1
%N A367582 Triangle read by rows where T(n,k) is the number of integer partitions of n whose multiset multiplicity kernel (in which each multiplicity becomes the least element of that multiplicity), sums to k.
%C A367582 We define the multiset multiplicity kernel MMK(m) of a multiset m by the following property, holding for all distinct multiplicities k >= 1. If S is the set of elements of multiplicity k in m, then min(S) has multiplicity |S| in MMK(m). For example, MMK({1,1,2,2,3,4,5}) = {1,1,3,3,3}, and MMK({1,2,3,4,5,5,5,5}) = {1,1,1,1,5}. As an operation on multisets, MMK is represented by A367579, and as an operation on their Heinz numbers, it is represented by A367580.
%e A367582 Triangle begins:
%e A367582   1
%e A367582   0  1
%e A367582   0  1  1
%e A367582   0  1  1  1
%e A367582   0  1  2  1  1
%e A367582   0  1  1  2  2  1
%e A367582   0  1  3  3  2  1  1
%e A367582   0  1  1  4  3  3  2  1
%e A367582   0  1  3  5  4  4  3  1  1
%e A367582   0  1  2  6  4  8  3  3  2  1
%e A367582   0  1  3  7  9  6  7  4  3  1  1
%e A367582   0  1  1  8  7 11  9  9  4  3  2  1
%e A367582   0  1  5 10 11 13 10 11  6  5  3  1  1
%e A367582   0  1  1 10 11 17 14 18 10  9  4  3  2  1
%e A367582   0  1  3 12 17 19 18 22 14 12  8  4  3  1  1
%e A367582   0  1  3 12 15 27 19 31 19 19 10  9  5  3  2  1
%e A367582   0  1  4 15 23 27 31 33 24 26 18 12  8  4  3  1  1
%e A367582   0  1  1 14 20 35 33 48 32 37 25 20 11 10  4  3  2  1
%e A367582 Row n = 7 counts the following partitions:
%e A367582   (1111111)  (61)  (421)     (52)     (4111)  (511)  (7)
%e A367582                    (2221)    (331)    (322)   (43)
%e A367582                    (22111)   (31111)  (3211)
%e A367582                    (211111)
%t A367582 mmk[q_]:=With[{mts=Length/@Split[q]}, Sort[Table[Min@@Select[q, Count[q,#]==i&], {i,mts}]]];
%t A367582 Table[Length[Select[IntegerPartitions[n], Total[mmk[#]]==k&]], {n,0,10}, {k,0,n}]
%Y A367582 Column k = 2 is A000005(n) - 1 = A032741(n).
%Y A367582 Row sums are A000041.
%Y A367582 The case of constant partitions is A051731, row sums A000005.
%Y A367582 The corresponding rank statistic is A367581, row sums of A367579.
%Y A367582 A072233 counts partitions by number of parts.
%Y A367582 A091602 counts partitions by greatest multiplicity, least A243978.
%Y A367582 A116608 counts partitions by number of distinct parts.
%Y A367582 A116861 counts partitions by sum of distinct parts.
%Y A367582 Cf. A000837, A056239, A066328, A071625, A072774, A082090, A367580.
%K A367582 nonn,tabl
%O A367582 0,13
%A A367582 _Gus Wiseman_, Nov 28 2023