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A341126
Number of partitions of n into 8 prime powers (including 1).
9
1, 1, 2, 3, 5, 6, 10, 13, 19, 23, 32, 38, 51, 60, 77, 90, 113, 128, 158, 179, 215, 240, 287, 316, 373, 409, 475, 517, 599, 645, 741, 799, 908, 971, 1104, 1173, 1326, 1408, 1580, 1670, 1874, 1967, 2198, 2310, 2563, 2680, 2976, 3097, 3426, 3566, 3926, 4070, 4485
OFFSET
8,3
MAPLE
q:= proc(n) option remember; nops(ifactors(n)[2])<2 end:
b:= proc(n, i, t) option remember; `if`(n=0,
`if`(t=0, 1, 0), `if`(i<1 or t<1, 0, b(n, i-1, t)+
`if`(q(i), b(n-i, min(n-i, i), t-1), 0)))
end:
a:= n-> b(n$2, 8):
seq(a(n), n=8..60); # Alois P. Heinz, Feb 05 2021
MATHEMATICA
q[n_] := q[n] = Length[FactorInteger[n]] < 2;
b[n_, i_, t_] := b[n, i, t] = If[n == 0,
If[t == 0, 1, 0], If[i < 1 || t < 1, 0, b[n, i - 1, t] +
If[q[i], b[n - i, Min[n - i, i], t - 1], 0]]];
a[n_] := b[n, n, 8];
Table[a[n], {n, 8, 60}] (* Jean-François Alcover, Feb 22 2022, after _Alois P. Heinz *)
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 05 2021
STATUS
approved