A090886 Primes in the products of consecutive prime-indexed primes + 2 or A080696(n) + 2.

5, 17, 167, 14093057717, 16192486429745837, 114681479899746991802547357477494807, 12994174855450524638613469509299054674461271855442034674644855689971858721497

Offset

1,1

Comments

These numbers, except for the first one, always end in 7.

The next term (a(8)) has 129 digits. - Harvey P. Dale, Apr 05 2019

Links

Amiram Eldar, Table of n, a(n) for n = 1..12

Mathematica

Select[FoldList[Times, Table[Prime[n], {n, Prime[Range[40]]}]]+2, PrimeQ] (* Harvey P. Dale, Apr 05 2019 *)

Prog

(PARI) piptorial2(n) = { y=1; for(x=1, n, v=prime(prime(x)); y*=v; if(isprime(y+2), print1(y+2", ")) ) }

Crossrefs

Cf. A080696, A087400.

Sequence in context: A286307 A119769 A182066 * A097490 A355277 A309178

Adjacent sequences: A090883 A090884 A090885 * A090887 A090888 A090889

Keyword

nonn

Author

Cino Hilliard, Feb 12 2004

Status

approved