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A274108 Number of partitions of n into parts with exactly two different sizes, the sizes being relatively prime. 3
0, 0, 1, 2, 5, 5, 11, 11, 16, 17, 27, 21, 37, 33, 38, 42, 59, 46, 71, 57, 70, 75, 97, 72, 104, 99, 109, 103, 141, 102, 157, 133, 148, 153, 166, 140, 207, 183, 192, 174, 241, 180, 259, 215, 223, 247, 295, 219, 300, 260, 292, 279, 353, 275, 336, 300, 346, 351 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

N. Benyahia Tani, S. Bouroubi, O. Kihel, An effective approach for integer partitions using exactly two distinct sizes of parts, Bulletin du Laboratoire, 03 (2015) 18 - 27.

EXAMPLE

Explanation of a(3)-a(6):

n=3: 21

n=4: 31, 211

n=5: 41, 32, 311, 221, 2111

n=6: 51, 411, 3111, 2211, 21111

CROSSREFS

Row sums of triangle in A274109.

Cf. A002133, A117955, A117956, A216665.

Sequence in context: A194119 A084721 A273041 * A138316 A183719 A239340

Adjacent sequences:  A274105 A274106 A274107 * A274109 A274110 A274111

KEYWORD

nonn,look

AUTHOR

N. J. A. Sloane, Jun 17 2016

EXTENSIONS

More terms from Alois P. Heinz, Jun 23 2016

STATUS

approved

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Last modified January 28 15:20 EST 2022. Contains 350657 sequences. (Running on oeis4.)