A347777 - OEIS

A347777

Number of compositions (ordered partitions) of n into at most 2 squarefree parts.

1, 1, 2, 3, 3, 3, 4, 5, 6, 4, 4, 5, 7, 7, 6, 7, 10, 9, 8, 7, 11, 9, 10, 9, 14, 10, 10, 10, 13, 11, 10, 11, 16, 13, 14, 13, 22, 15, 14, 15, 22, 17, 16, 19, 25, 20, 16, 17, 26, 20, 16, 15, 27, 21, 20, 15, 26, 21, 22, 19, 29, 23, 22, 22, 30, 23, 22, 23, 35, 25, 26

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OFFSET

0,3

LINKS

Table of n, a(n) for n=0..70.

MATHEMATICA

Table[Length@Flatten[Permutations/@IntegerPartitions[n, 2, Select[Range@n, SquareFreeQ]], 1], {n, 0, 100}] (* Giorgos Kalogeropoulos, Sep 13 2021 *)

CROSSREFS

Cf. A005117, A098235, A280194, A347778, A347779, A347780.

Sequence in context: A267098 A304110 A051134 * A037458 A296816 A064474

Adjacent sequences: A347774 A347775 A347776 * A347778 A347779 A347780

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Sep 13 2021

STATUS

approved