A393971 Number of partitions p of n into distinct parts such that max(p) <= 3*min(p).

1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 6, 6, 6, 7, 9, 10, 10, 11, 12, 15, 16, 17, 19, 21, 23, 25, 29, 30, 33, 37, 40, 43, 47, 51, 55, 61, 65, 71, 77, 83, 89, 97, 103, 112, 122, 131, 141, 151, 161, 173, 188, 199, 214, 230, 247, 264, 282, 300, 320, 344, 366, 391, 417, 445, 474, 505

Offset

1,3

Links

Table of n, a(n) for n=1..66.

Formula

G.f.: Sum_{j>=1} q^j * Product_{k=j+1..3*j} (1+q^k).

Crossrefs

Cf. A241061, A241063, A393970.

Sequence in context: A199575 A120187 A029062 * A219502 A219704 A253144

Adjacent sequences: A393968 A393969 A393970 * A393972 A393973 A393974

Keyword

nonn

Author

Seiichi Manyama, Mar 05 2026

Status

approved