A275029 Partition numbers (A000041) congruent to 2 (mod 4).

2, 22, 30, 42, 490, 1002, 1958, 3010, 3718, 6842, 12310, 37338, 53174, 89134, 105558, 124754, 204226, 614154, 1741630, 2012558, 13848650, 34262962, 133230930, 214481126, 271248950, 607163746, 4835271870, 30388671978, 45060624582, 88751778802, 107438159466

Offset

1,1

Comments

Partition numbers having the same number of even divisors as odd divisors.

The corresponding indices are in A237280.

The intersection of A000041 and A016825.

Links

Robert Israel, Table of n, a(n) for n = 1..500

Example

30 is in the sequence because it is a partition number, and its divisors are [1,2,3,5,6,10,15,30].

Maple

select(t -> t mod 4 = 2, map(combinat:-numbpart, [$1..500])); # Robert Israel, Nov 14 2016

Mathematica

Select[PartitionsP@ Range@ 160, Mod[#, 4] == 2 &] (* Michael De Vlieger, Nov 15 2016 *)

Prog

(PARI) a000041(n) = numbpart(n)
terms(n) = my(i=0, k=2); while(1, if(Mod(a000041(k), 4)==2, print1(a000041(k), ", "); i++); if(i==n, break); k++)
/* Print initial 50 terms as follows */
terms(50) \\ Felix Fröhlich, Nov 15 2016

Crossrefs

Cf. A000041, A016825, A213179, A237280.

Sequence in context: A053962 A111771 A052001 * A085185 A166726 A156441

Adjacent sequences: A275026 A275027 A275028 * A275030 A275031 A275032

Keyword

nonn

Author

Colin Barker, Nov 13 2016

Status

approved