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A341137
Number of ways to write n as an ordered sum of 8 prime powers (including 1).
7
1, 8, 36, 120, 330, 784, 1660, 3208, 5763, 9752, 15724, 24368, 36520, 53152, 75392, 104464, 141717, 188624, 246836, 318088, 404356, 507656, 630172, 774048, 941685, 1135304, 1357652, 1611240, 1899138, 2224016, 2589352, 2997544, 3452619, 3957480, 4516912, 5134096, 5815338
OFFSET
8,2
MAPLE
q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, t) option remember;
`if`(n=0, `if`(t=0, 1, 0), `if`(t<1, 0, add(
`if`(q(j), b(n-j, t-1), 0), j=1..n)))
end:
a:= n-> b(n, 8):
seq(a(n), n=8..44); # Alois P. Heinz, Feb 05 2021
MATHEMATICA
nmax = 44; CoefficientList[Series[Sum[Boole[PrimePowerQ[k] || k == 1] x^k, {k, 1, nmax}]^8, {x, 0, nmax}], x] // Drop[#, 8] &
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 05 2021
STATUS
approved