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A341486 Number of ways to write n as an ordered sum of 9 nonprime numbers. 7
1, 0, 0, 9, 0, 9, 36, 9, 81, 93, 108, 333, 270, 585, 945, 1047, 2016, 2547, 3612, 5571, 7101, 10227, 14256, 18621, 25830, 34497, 44955, 60610, 78480, 101754, 133092, 169380, 217008, 276852, 347967, 439272, 549786, 683244, 849528, 1047678, 1288017, 1577934 (list; graph; refs; listen; history; text; internal format)
OFFSET

9,4

LINKS

Table of n, a(n) for n=9..50.

MAPLE

b:= proc(n, t) option remember;

      `if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(

      `if`(isprime(j), 0, b(n-j, t-1)), j=1..n)))

    end:

a:= n-> b(n, 9):

seq(a(n), n=9..50);  # Alois P. Heinz, Feb 13 2021

MATHEMATICA

nmax = 50; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^k, {k, 1, nmax}]^9, {x, 0, nmax}], x] // Drop[#, 9] &

CROSSREFS

Cf. A005171, A018252, A052284, A076608, A340965, A341457, A341468, A341480, A341481, A341482, A341483, A341484, A341485.

Sequence in context: A332093 A151949 A056965 * A320379 A308102 A338016

Adjacent sequences:  A341483 A341484 A341485 * A341487 A341488 A341489

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Feb 13 2021

STATUS

approved

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Last modified August 3 17:21 EDT 2021. Contains 346439 sequences. (Running on oeis4.)