A028369 a(n) = 2^(2^(n-1) + n - 2).

1, 4, 32, 1024, 524288, 68719476736, 590295810358705651712, 21778071482940061661655974875633165533184, 14821387422376473014217086081112052205218558037201992197050570753012880593911808

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..12

Programs

Magma

[2^(n-1)*2^(2^(n-1)-1): n in [1..10]]; // Vincenzo Librandi, Jun 03 2011

Mathematica

Table[2^(2^(n-1)+n-2),{n,10}] (* Harvey P. Dale, Aug 20 2019 *)

PARI

a(n)=1<<(2^(n-1)+n-2) \\ Charles R Greathouse IV, Jun 05 2011

Formula

a(n) = 2^A052944(n-1). - R. J. Mathar, Dec 15 2015

Extensions

One more term (a(9)) from Harvey P. Dale, Aug 20 2019