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A341482
Number of ways to write n as an ordered sum of 5 nonprime numbers.
8
1, 0, 0, 5, 0, 5, 10, 5, 25, 15, 30, 55, 45, 85, 105, 126, 180, 220, 260, 360, 415, 510, 650, 745, 915, 1101, 1270, 1525, 1800, 2045, 2440, 2780, 3225, 3660, 4250, 4771, 5465, 6185, 6930, 7840, 8816, 9790, 11015, 12240, 13505, 15146, 16595, 18385, 20240, 22325, 24255
OFFSET
5,4
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, 5):
seq(a(n), n=5..55); # Alois P. Heinz, Feb 13 2021
MATHEMATICA
nmax = 55; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^k, {k, 1, nmax}]^5, {x, 0, nmax}], x] // Drop[#, 5] &
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 13 2021
STATUS
approved