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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
OFFSET
9,4
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] &
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 13 2021
STATUS
approved