A177026 Primes of the form 4^k*(2^k-1)+1.

5, 449, 144114913197948929, 5070602400617769700807459995649, 11417981541647673977863886842678355104249151489

Offset

1,1

Comments

a(6) has 288 digits.

Links

Table of n, a(n) for n=1..5.

Formula

a(n) = 8^A098856(n)-4^A098856(n)+1.

Prog

(Magma) [a: n in [0..350]|IsPrime(a) where a is 8^n-4^n+1^n];

Crossrefs

Cf. A098856, A155629

Sequence in context: A317345 A333263 A212042 * A300544 A055305 A300971

Adjacent sequences: A177023 A177024 A177025 * A177027 A177028 A177029

Keyword

nonn,less

Author

Vincenzo Librandi, Dec 09 2010

Status

approved