A063486 a(n) = 2^(2^n) + 5.

7, 9, 21, 261, 65541, 4294967301, 18446744073709551621, 340282366920938463463374607431768211461, 115792089237316195423570985008687907853269984665640564039457584007913129639941

Offset

0,1

References

D. M. Burton, Elementary Number Theory, Allyn and Bacon Inc., Boston, MA, 1976, p. 238.

Links

Harry J. Smith, Table of n, a(n) for n=0..11

Tigran Hakobyan, On the unboundedness of common divisors of distinct terms of the sequence a(n)=2^2^n+d for d>1, arXiv:1601.04946 [math.NT], 2016.

Mathematica

2^2^Range[0, 10] + 5 (* Paolo Xausa, Apr 17 2024 *)

Prog

(PARI) for(n=0, 8, print1(2^(2^n)+5), ", ")
(PARI) { for (n=0, 11, write("b063486.txt", n, " ", 2^(2^n) + 5) ) } \\ Harry J. Smith, Aug 23 2009

Crossrefs

Cf. A000215, A001146, A130729, A130730.

Sequence in context: A147012 A032394 A242988 * A070423 A018882 A257332

Adjacent sequences: A063483 A063484 A063485 * A063487 A063488 A063489

Keyword

easy,nonn,changed

Author

Jason Earls, Jul 28 2001

Status

approved