OFFSET
0,1
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..1000
FORMULA
G.f.: ((1/x)*Sum_{k>=1} prime(k)*x^k)^4. - Ilya Gutkovskiy, Mar 10 2018
MAPLE
b:= proc(n, k) option remember; `if`(k=1, ithprime(n+1),
add(b(j, floor(k/2))*b(n-j, ceil(k/2)), j=0..n))
end:
a:= n-> b(n, 4):
seq(a(n), n=0..35); # Alois P. Heinz, Mar 10 2018
MATHEMATICA
b[n_, k_] := b[n, k] = If[k==1, Prime[n+1], Sum[b[j, Floor[k/2]] b[n-j, Ceiling[k/2]], {j, 0, n}]];
a[n_] := b[n, 4];
a /@ Range[0, 35] (* Jean-François Alcover, Nov 16 2020, after Alois P. Heinz *)
PROG
(PARI) my(N = 50, x = 'x + O('x^N)); Vec(((1/x)*sum(k=1, N, prime(k)*x^k))^4) \\ Michel Marcus, Mar 10 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved