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A344782 Number of compositions of the n-th prime into a prime number of prime parts. 3
0, 0, 2, 5, 11, 23, 119, 237, 776, 6665, 16518, 207953, 892680, 1824445, 8374988, 96208461, 978217302, 2059770725, 18616884428, 78013141907, 158103168924, 1386674113487, 6734724875544, 82189835767618, 2013603833805429, 9101106147506177, 19147196940580651 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..300

EXAMPLE

a(3) = 2: [2,3], [3,2].

a(4) = 5: [5,2], [2,5], [3,2,2], [2,3,2], [2,2,3].

MAPLE

b:= proc(n, c) option remember; `if`(n=0, `if`(isprime(c),

      1, 0), add(`if`(isprime(j), b(n-j, c+1), 0), j=2..n))

    end:

a:= n-> b(ithprime(n), 0):

seq(a(n), n=1..31);

CROSSREFS

Cf. A000040, A316154, A344790.

Sequence in context: A192415 A201779 A067149 * A191240 A208952 A091358

Adjacent sequences:  A344779 A344780 A344781 * A344783 A344784 A344785

KEYWORD

nonn

AUTHOR

Alois P. Heinz, May 28 2021

STATUS

approved

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Last modified November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)