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A101049 Number of partitions of n into parts having at most two prime-factors. 5
1, 2, 3, 5, 7, 11, 15, 21, 29, 40, 53, 71, 93, 122, 158, 203, 259, 329, 415, 521, 651, 809, 1001, 1234, 1515, 1853, 2258, 2743, 3321, 4009, 4825, 5791, 6932, 8277, 9859, 11715, 13889, 16431, 19398, 22854, 26873, 31539, 36949, 43210, 50446, 58796, 68419 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..47.

EXAMPLE

n=10 has two partitions with parts having more than two

prime-factors: 10 = 2*2*2 + 2 = 2*2*2 + 1 + 1, therefore

a(10) = A000041(10) - 2 = 42 - 2 = 40.

CROSSREFS

Cf. A000041, A101048, A037143, A101040.

Sequence in context: A232480 A035977 A288256 * A035986 A035996 A261775

Adjacent sequences:  A101046 A101047 A101048 * A101050 A101051 A101052

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Nov 28 2004

STATUS

approved

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Last modified January 28 22:35 EST 2020. Contains 331328 sequences. (Running on oeis4.)