A367189 Number of partitions of 2n into n divisors of 2n.

1, 1, 1, 2, 2, 2, 8, 2, 4, 9, 9, 2, 36, 2, 10, 45, 12, 2, 104, 2, 54, 69, 15, 2, 289, 15, 16, 100, 83, 2, 1322, 2, 47, 136, 21, 99, 1963, 2, 22, 179, 568, 2, 3168, 2, 158, 3159, 27, 2, 4637, 23, 480, 282, 207, 2, 6579, 189, 1046, 343, 33, 2, 82522, 2, 34, 7361

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..1000

Formula

a(n) = A320638(2n,n).

a(n) = 2 <=> n = 4 or n in { A065091 }.

Example

a(6) = 8: 222222, 322221, 332211, 333111, 422211, 432111, 441111, 621111.
a(7) = 2: 2222222, 7211111.
a(8) = 4: 22222222, 42222211, 44221111, 82111111.
a(9) = 9: 222222222, 322222221, 332222211, 333222111, 333321111, 622221111, 632211111, 633111111, 921111111.
a(10) = 9: 2222222222, 4222222211, 4422221111, 4442111111, 5222222111, 5422211111, 5441111111, 5522111111, (10)211111111.

Crossrefs

Cf. A065091, A320638.

Sequence in context: A137508 A055921 A029605 * A054271 A278245 A321026

Adjacent sequences: A367186 A367187 A367188 * A367190 A367191 A367192

Keyword

nonn

Author

Alois P. Heinz, Nov 08 2023

Status

approved