A052449 a(n) = 1 + Product_{k=1..n} Fibonacci(k).

2, 2, 3, 7, 31, 241, 3121, 65521, 2227681, 122522401, 10904493601, 1570247078401, 365867569267201, 137932073613734401, 84138564904377984001, 83044763560621070208001, 132622487406311849122176001, 342696507457909818131702784001

Offset: 1

Author

Eric W. Weisstein

Keywords

• nonn

Comments

The first 8 terms are primes. - Jonathan Vos Post, Dec 08 2012

a(22) and a(28) are also primes. - Robert Israel, Jun 10 2015

There are no further primes up to a(300). - Harvey P. Dale, Feb 28 2023

Links

• Robert Israel, Table of n, a(n) for n = 1..93
• Eric Weisstein's World of Mathematics, Fibonacci Number.

Crossrefs

Cf. A000045, A003266, A053413, A053408.

Programs

GAP

List([1..20], n-> 1+Product([1..n], j-> Fibonacci(j)) ); # G. C. Greubel, Sep 26 2019

Magma

[1+(&*[Fibonacci(j): j in [1..n]]): n in [1..20]]; // G. C. Greubel, Sep 26 2019

Maple

seq(1+mul(combinat:-fibonacci(j),j=1..n), n=1..30); # Robert Israel, Jun 10 2015

Mathematica

1 + Table[Times @@ Fibonacci[Range[n]], {n, 20}] (* T. D. Noe, Dec 29 2012 *)
FoldList[Times,Fibonacci[Range[20]]]+1 (* Harvey P. Dale, Feb 28 2023 *)

PARI

vector(20, n, 1+prod(j=1,n, fibonacci(j))) \\ G. C. Greubel, Sep 26 2019

Sage

[1+product(fibonacci(j) for j in (1..n)) for n in (1..20)] # G. C. Greubel, Sep 26 2019

Formula

a(n) = A003266(n)+1. - Robert Israel, Jun 10 2015