A347745 Number of compositions (ordered partitions) of n into at most 3 noncomposite parts.

1, 1, 2, 4, 6, 9, 10, 12, 13, 15, 15, 16, 13, 18, 17, 24, 19, 25, 18, 30, 24, 36, 23, 37, 23, 44, 29, 45, 19, 43, 20, 54, 30, 54, 25, 60, 29, 67, 29, 60, 21, 70, 28, 78, 38, 77, 31, 88, 33, 95, 44, 91, 30, 100, 30, 110, 42, 97, 25, 109, 35, 129, 49, 113, 31, 135

Offset: 0

Author

Ilya Gutkovskiy, Sep 11 2021

Keywords

• nonn

Comments

"Noncomposite" means "1 or a prime".

Crossrefs

Cf. A008578, A280917, A283762, A347740, A347744.

Programs

Mathematica

Table[Length@Flatten[Permutations/@IntegerPartitions[n,3,Join[{1},Prime@Range@PrimePi@n]],1],{n,0,65}] (* Giorgos Kalogeropoulos, Sep 12 2021 *)