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A341140 Number of partitions of n into 3 distinct prime powers (including 1). 8
1, 1, 2, 2, 3, 3, 5, 5, 7, 6, 8, 7, 8, 8, 10, 10, 12, 11, 12, 12, 13, 12, 16, 15, 15, 16, 18, 17, 19, 20, 21, 24, 22, 22, 23, 25, 22, 27, 26, 25, 26, 29, 25, 31, 27, 30, 31, 34, 26, 34, 31, 35, 32, 38, 29, 40, 32, 36, 34, 41, 29, 44, 35, 41, 36, 47, 34, 51, 38, 45, 41, 54 (list; graph; refs; listen; history; text; internal format)
OFFSET

6,3

LINKS

Table of n, a(n) for n=6..77.

MAPLE

q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:

b:= proc(n, i, t) option remember; `if`(n=0,

      `if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+

      `if`(q(i), b(n-i, min(n-i, i-1), t-1), 0)))

    end:

a:= n-> b(n$2, 3):

seq(a(n), n=6..77);  # Alois P. Heinz, Feb 05 2021

CROSSREFS

Cf. A000961, A010055, A282064, A307727, A307825, A341112, A341132, A341141, A341142, A341143, A341144, A341145.

Sequence in context: A179254 A304430 A086609 * A340285 A341462 A035031

Adjacent sequences:  A341137 A341138 A341139 * A341141 A341142 A341143

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Feb 05 2021

STATUS

approved

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Last modified June 12 13:21 EDT 2021. Contains 344947 sequences. (Running on oeis4.)