A128944 Numbers n such that the smallest prime > 2^n is a twin prime member.

1, 2, 3, 4, 9, 10, 16, 23, 229, 245, 266, 338, 628, 4118

Offset

1,2

Links

Table of n, a(n) for n=1..14.

Formula

A014210(a(n)) = A128949(n).

Example

For n=4, 17 is the smallest prime > 2^4 and is a member of the twin prime pair 17, 19.

Mathematica

Select[Range[4200], AnyTrue[NextPrime[2^#]+{2, -2}, PrimeQ]&] (* Harvey P. Dale, Mar 07 2023 *)

Prog

(PARI) g(n, b)=for(x=1, n, y=nextprime(b^x); if(ispseudoprime(y+2), print1(x", ")))

Crossrefs

Sequence in context: A098551 A249943 A251620 * A295969 A174437 A127150

Adjacent sequences: A128941 A128942 A128943 * A128945 A128946 A128947

Keyword

hard,more,nonn

Author

Cino Hilliard, Apr 28 2007

Extensions

Edited by Ray Chandler, May 12 2007

One more term from Ryan Propper, Jan 03 2008

Status

approved