OFFSET
6,4
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, 6):
seq(a(n), n=6..53); # Alois P. Heinz, Feb 13 2021
MATHEMATICA
nmax = 53; CoefficientList[Series[Sum[Boole[!PrimeQ[k]] x^k, {k, 1, nmax}]^6, {x, 0, nmax}], x] // Drop[#, 6] &
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 13 2021
STATUS
approved