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A341485
Number of ways to write n as an ordered sum of 8 nonprime numbers.
7
1, 0, 0, 8, 0, 8, 28, 8, 64, 64, 84, 232, 182, 400, 596, 680, 1232, 1520, 2128, 3144, 3970, 5504, 7532, 9584, 12945, 16920, 21464, 28288, 35778, 45264, 57856, 72024, 90036, 112456, 138140, 170600, 208874, 254192, 309088, 373584, 449731, 539408, 645584, 767776
OFFSET
8,4
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, 8):
seq(a(n), n=8..51); # Alois P. Heinz, Feb 13 2021
MATHEMATICA
nmax = 51; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^k, {k, 1, nmax}]^8, {x, 0, nmax}], x] // Drop[#, 8] &
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 13 2021
STATUS
approved