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A341980
Number of partitions of n into 9 distinct primes (counting 1 as a prime).
4
1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 2, 0, 3, 0, 1, 0, 3, 0, 5, 0, 4, 1, 6, 0, 10, 0, 6, 1, 11, 1, 16, 1, 11, 2, 19, 2, 25, 1, 18, 5, 32, 4, 36, 2, 32, 9, 47, 7, 55, 7, 49, 14, 69, 10, 80, 12, 74, 22, 98, 19, 117, 22, 106, 34, 140, 31, 158, 32, 149, 54, 194, 48, 215, 50
OFFSET
78,11
MAPLE
b:= proc(n, i) option remember; series(`if`(n=0, 1,
`if`(i<0, 0, (p-> `if`(p>n, 0, x*b(n-p, i-1)))(
`if`(i=0, 1, ithprime(i)))+b(n, i-1))), x, 10)
end:
a:= n-> coeff(b(n, numtheory[pi](n)), x, 9):
seq(a(n), n=78..151); # Alois P. Heinz, Feb 24 2021
MATHEMATICA
b[n_, i_] := b[n, i] = Series[If[n == 0, 1,
If[i < 0, 0, Function[p, If[p > n, 0, x*b[n - p, i - 1]]][
If[i == 0, 1, Prime[i]]] + b[n, i - 1]]], {x, 0, 10}];
a[n_] := Coefficient[b[n, PrimePi[n]], x, 9];
Table[a[n], {n, 78, 151}] (* Jean-François Alcover, Feb 24 2022, after Alois P. Heinz *)
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Feb 24 2021
STATUS
approved