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A350944 Heinz numbers of integer partitions of which the number of odd parts is equal to the number of odd conjugate parts.

%I A350944 #5 Jan 29 2022 12:49:45
%S A350944 1,2,6,9,10,12,15,18,20,30,35,49,54,55,56,70,75,77,81,84,88,90,98,108,
%T A350944 110,112,125,132,135,143,154,162,168,169,176,180,187,210,221,260,264,
%U A350944 270,286,294,315,323,330,338,340,350,361,363,364,374,391,416,420
%N A350944 Heinz numbers of integer partitions of which the number of odd parts is equal to the number of odd conjugate parts.
%C A350944 The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
%F A350944 A257991(a(n)) = A344616(a(n)).
%e A350944 The terms together with their prime indices begin:
%e A350944    1: ()
%e A350944    2: (1)
%e A350944    6: (2,1)
%e A350944    9: (2,2)
%e A350944   10: (3,1)
%e A350944   12: (2,1,1)
%e A350944   15: (3,2)
%e A350944   18: (2,2,1)
%e A350944   20: (3,1,1)
%e A350944   30: (3,2,1)
%e A350944   35: (4,3)
%e A350944   49: (4,4)
%e A350944   54: (2,2,2,1)
%t A350944 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A350944 conj[y_]:=If[Length[y]==0,y,Table[Length[Select[y,#>=k&]],{k,1,Max[y]}]];
%t A350944 Select[Range[100],Count[conj[primeMS[#]],_?OddQ]==Count[primeMS[#],_?OddQ]&]
%Y A350944 These partitions are counted by A277103.
%Y A350944 The even rank case is A345196.
%Y A350944 The conjugate version is A350943, counted by A277579.
%Y A350944 These are the positions of 0's in A350951, even A350950.
%Y A350944 A000041 = integer partitions, strict A000009.
%Y A350944 A056239 adds up prime indices, counted by A001222, row sums of A112798.
%Y A350944 A122111 = conjugation using Heinz numbers.
%Y A350944 A257991 = # of odd parts, conjugate A344616.
%Y A350944 A257992 = # of even parts, conjugate A350847.
%Y A350944 A316524 = alternating sum of prime indices.
%Y A350944 The following rank partitions:
%Y A350944   A325040: product = product of conjugate, counted by A325039.
%Y A350944   A325698: # of even parts = # of odd parts, counted by A045931.
%Y A350944   A349157: # of even parts = # of odd conjugate parts, counted by A277579.
%Y A350944   A350848: # even conj parts = # odd conj parts, counted by A045931.
%Y A350944   A350945: # of even parts = # of even conjugate parts, counted by A350948.
%Y A350944 Cf. A000070, A000700, A027187, A027193, A103919, A236559, A350942.
%K A350944 nonn
%O A350944 1,2
%A A350944 _Gus Wiseman_, Jan 28 2022