login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A014344
Four-fold convolution of primes with themselves.
2
16, 96, 376, 1160, 3121, 7532, 16754, 34796, 68339, 127952, 229956, 398688, 669781, 1094076, 1742710, 2713604, 4139111, 6195712, 9115304, 13199072, 18833449, 26509260, 36843322, 50603884, 68740107, 92414192, 123039628, 162323200, 212312453, 275448380
OFFSET
0,1
LINKS
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
Column k=4 of A340991.
Sequence in context: A143060 A006637 A241937 * A239613 A100313 A091079
KEYWORD
nonn
STATUS
approved