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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.

A350849 Number of odd conjugate parts minus number of even parts in the integer partition with Heinz number n.

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%I A350849 #10 Jan 29 2022 12:49:17
%S A350849 0,1,1,0,3,0,3,1,-2,2,5,1,5,2,0,0,7,-1,7,3,0,4,9,0,0,4,-1,3,9,1,11,1,
%T A350849 2,6,0,-2,11,6,2,2,13,1,13,5,1,8,15,1,-2,1,4,5,15,-2,2,2,4,8,17,0,17,
%U A350849 10,1,0,2,3,19,7,6,1,19,-1,21,10,1,7,0,3,21,3
%N A350849 Number of odd conjugate parts minus number of even parts in the integer partition with Heinz number n.
%C A350849 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 A350849 a(n) = A344616(n) - A257992(n).
%e A350849 First positions n such that a(n) = 4, 3, 2, 1, 0, -1, -2, -3, -4, together with their prime indices, are:
%e A350849    22: (5,1)
%e A350849     5: (3)
%e A350849    10: (3,1)
%e A350849     2: (1)
%e A350849     1: ()
%e A350849    18: (2,2,1)
%e A350849     9: (2,2)
%e A350849   162: (2,2,2,2,1)
%e A350849    81: (2,2,2,2)
%t A350849 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A350849 conj[y_]:=If[Length[y]==0,y,Table[Length[Select[y,#>=k&]],{k,1,Max[y]}]];
%t A350849 Table[Count[conj[primeMS[n]],_?OddQ]-Count[primeMS[n],_?EvenQ],{n,100}]
%Y A350849 This is a hybrid of A195017 and A350941.
%Y A350849 Positions of 0's are A349157.
%Y A350849 Counting even conjugate parts instead of even parts gives A350941.
%Y A350849 The conjugate version is A350942.
%Y A350849 A257991 counts odd parts, conjugate A344616.
%Y A350849 A257992 counts even parts, conjugate A350847.
%Y A350849 The following rank partitions:
%Y A350849   A325698: # of even parts = # of odd parts.
%Y A350849   A349157: # of even parts = # of odd conjugate parts, counted by A277579.
%Y A350849   A350848: # even conj parts = # odd conj parts, counted by A045931.
%Y A350849   A350943: # of even conjugate parts = # of odd parts, counted by A277579.
%Y A350849   A350944: # of odd parts = # of odd conjugate parts, counted by A277103.
%Y A350849   A350945: # of even parts = # of even conjugate parts, counted by A350948.
%Y A350849 A000041 = integer partitions, strict A000009.
%Y A350849 A056239 adds up prime indices, counted by A001222, row sums of A112798.
%Y A350849 A122111 represents conjugation using Heinz numbers.
%Y A350849 A316524 = alternating sum of prime indices.
%Y A350849 Cf. A026424, A028260, A130780, A171966, A239241, A241638, A325700, A350947, A350949, A350950, A350951.
%K A350849 sign
%O A350849 1,5
%A A350849 _Gus Wiseman_, Jan 28 2022