A100497 Numbers n such that (2^n+1)^4-2 is a semiprime.

0, 2, 3, 4, 6, 8, 10, 12, 16, 19, 22, 43, 44, 45, 52, 67, 76, 117, 130, 151, 169, 208, 232, 262

Offset

1,2

Comments

a(20) >= 151. - Hugo Pfoertner, Jul 24 2019

a(25) >= 361. - Tyler Busby, Feb 17 2023

Links

Table of n, a(n) for n=1..24.

Status of (2^361+1)^4-2 in factordb.com.

Mathematica

Select[Range[0, 130], PrimeOmega[(2^#+1)^4-2]==2&] (* Harvey P. Dale, Sep 02 2016 *)

Crossrefs

Cf. A100496, n such that (2^n+1)^4-2 is prime.

Sequence in context: A002093 A179971 A067069 * A191283 A341016 A200678

Adjacent sequences: A100494 A100495 A100496 * A100498 A100499 A100500

Keyword

nonn,more,hard

Author

Jonathan Vos Post, Nov 23 2004

Extensions

Corrected by Hugo Pfoertner, Nov 25 2004

a(20)-a(24) from Tyler Busby, Feb 17 2023

Status

approved