A347764 Number of compositions (ordered partitions) of n into at most 4 prime powers (including 1).

1, 1, 2, 4, 8, 15, 25, 40, 59, 81, 106, 136, 170, 208, 251, 294, 339, 383, 431, 476, 530, 583, 642, 696, 757, 804, 866, 914, 980, 1041, 1125, 1167, 1256, 1312, 1405, 1466, 1598, 1657, 1790, 1840, 1961, 2004, 2148, 2160, 2335, 2365, 2505, 2502, 2707, 2664, 2884

Offset

0,3

Links

Table of n, a(n) for n=0..50.

Mathematica

Table[Length@Flatten[Permutations/@IntegerPartitions[n, 4, Join[{1}, Select[Range@n, PrimePowerQ]]], 1], {n, 0, 50}] (* Giorgos Kalogeropoulos, Sep 12 2021 *)

Crossrefs

Cf. A000961, A280543, A341133, A347762, A347763.

Sequence in context: A082562 A159243 A325840 * A324740 A262146 A089140

Adjacent sequences: A347761 A347762 A347763 * A347765 A347766 A347767

Keyword

nonn

Author

Ilya Gutkovskiy, Sep 12 2021

Status

approved