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

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, 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, 10, 1, 0, 2, 3, 19, 7, 6, 1, 19, -1, 21, 10, 1, 7, 0, 3, 21, 3

Offset: 1

Author

Gus Wiseman, Jan 28 2022

Keywords

• sign

Comments

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.

Examples

			First positions n such that a(n) = 4, 3, 2, 1, 0, -1, -2, -3, -4, together with their prime indices, are:
   22: (5,1)
    5: (3)
   10: (3,1)
    2: (1)
    1: ()
   18: (2,2,1)
    9: (2,2)
  162: (2,2,2,2,1)
   81: (2,2,2,2)
		

Crossrefs

This is a hybrid of A195017 and A350941.

Positions of 0's are A349157.

Counting even conjugate parts instead of even parts gives A350941.

The conjugate version is A350942.

A257991 counts odd parts, conjugate A344616.

A257992 counts even parts, conjugate A350847.

The following rank partitions:

A325698: # of even parts = # of odd parts.

A349157: # of even parts = # of odd conjugate parts, counted by A277579.

A350848: # even conj parts = # odd conj parts, counted by A045931.

A350943: # of even conjugate parts = # of odd parts, counted by A277579.

A350944: # of odd parts = # of odd conjugate parts, counted by A277103.

A350945: # of even parts = # of even conjugate parts, counted by A350948.

A000041 = integer partitions, strict A000009.

A056239 adds up prime indices, counted by A001222, row sums of A112798.

A122111 represents conjugation using Heinz numbers.

A316524 = alternating sum of prime indices.

Cf. A026424, A028260, A130780, A171966, A239241, A241638, A325700, A350947, A350949, A350950, A350951.

Programs

Mathematica

primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
conj[y_]:=If[Length[y]==0,y,Table[Length[Select[y,#>=k&]],{k,1,Max[y]}]];
Table[Count[conj[primeMS[n]],?OddQ]-Count[primeMS[n],?EvenQ],{n,100}]

Formula

a(n) = A344616(n) - A257992(n).