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A023615
Convolution of Fibonacci numbers and primes.
2
2, 5, 12, 24, 47, 84, 148, 251, 422, 702, 1155, 1894, 3090, 5027, 8164, 13244, 21467, 34772, 56306, 91149, 147528, 238756, 386367, 625212, 1011676, 1636989, 2648768, 4285864, 6934741, 11220718, 18155586, 29376435, 47532158, 76908732, 124441039, 201349922
OFFSET
0,1
LINKS
FORMULA
a(n) = Sum_{1<=k<=n+1} A000040(k)*A000045(n+2-k). - Robert Israel, Jan 18 2018
a(n) = a(n-1) + a(n-2) + prime(n+1). - Alois P. Heinz, Feb 19 2023
MAPLE
N:= 100: # to get a(0)..a(N)
G:= add(ithprime(i)*x^(i-1), i=1..N+1):
S:= series(G /(1-x-x^2), x, N+1):
seq(coeff(S, x, n), n=0..N); # Robert Israel, Jan 18 2018
# second Maple program:
a:= proc(n) option remember; `if`(n<0, 0,
a(n-1)+a(n-2)+ithprime(n+1))
end:
seq(a(n), n=0..35); # Alois P. Heinz, Feb 19 2023
CROSSREFS
KEYWORD
nonn
STATUS
approved