cp's OEIS Frontend

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.

A350950 Number of even parts minus number of even conjugate parts in the integer partition with Heinz number n.

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%I A350950 #5 Mar 18 2022 00:20:38
%S A350950 0,0,1,-1,0,0,1,0,0,-1,0,1,1,0,-1,-1,0,1,1,0,0,1,0,0,-3,0,3,1,1,0,0,0,
%T A350950 -1,-1,-2,0,1,0,0,-1,0,1,1,0,2,-1,0,1,-2,-2,-1,1,1,2,-3,0,0,0,0,-1,1,
%U A350950 -1,3,-1,-2,0,0,0,-1,-1,1,1,0,0,0,1,-3,1,1,0
%N A350950 Number of even parts minus number of even conjugate parts in the integer partition with Heinz number n.
%C A350950 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 A350950 a(n) = A257992(n) - A350847(n).
%F A350950 a(A122111(n)) = -a(n), where A122111 represents partition conjugation.
%e A350950 The prime indices of 78 are (6,2,1), with conjugate (3,2,1,1,1,1), so a(78) = 2 - 1 = 1.
%t A350950 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A350950 conj[y_]:=If[Length[y]==0,y,Table[Length[Select[y,#>=k&]],{k,1,Max[y]}]];
%t A350950 Table[Count[primeMS[n],_?EvenQ]-Count[conj[primeMS[n]],_?EvenQ],{n,100}]
%Y A350950 The version comparing even with odd parts is A195017.
%Y A350950 The version comparing even with odd conjugate parts is A350849.
%Y A350950 The version comparing even conjugate with odd conjugate parts is A350941.
%Y A350950 The version comparing odd with even conjugate parts is A350942.
%Y A350950 Positions of 0's are A350945, counted by A350948.
%Y A350950 The version comparing odd with odd conjugate parts is A350951.
%Y A350950 There are four individual statistics:
%Y A350950 - A257991 counts odd parts, conjugate A344616.
%Y A350950 - A257992 counts even parts, conjugate A350847.
%Y A350950 There are five other possible pairings of statistics:
%Y A350950 - A325698: # of even parts = # of odd parts, counted by A045931.
%Y A350950 - A349157: # of even parts = # of odd conjugate parts, counted by A277579.
%Y A350950 - A350848: # of even conj parts = # of odd conj parts, counted by A045931.
%Y A350950 - A350943: # of even conjugate parts = # of odd parts, counted by A277579.
%Y A350950 - A350944: # of odd parts = # of odd conjugate parts, counted by A277103.
%Y A350950 There are three possible double-pairings of statistics:
%Y A350950 - A350946, counted by A351977.
%Y A350950 - A350949, counted by A351976.
%Y A350950 - A351980, counted by A351981.
%Y A350950 The case of all four statistics equal is A350947, counted by A351978.
%Y A350950 A056239 adds up prime indices, counted by A001222, row sums of A112798.
%Y A350950 A116482 counts partitions by number of even parts.
%Y A350950 A122111 represents partition conjugation using Heinz numbers.
%Y A350950 A316524 gives the alternating sum of prime indices.
%Y A350950 Cf. A028260, A088218, A098123, A236559, A239241, A241638, A325700, A347450.
%K A350950 sign
%O A350950 1,25
%A A350950 _Gus Wiseman_, Mar 14 2022