A054650 Nearest integer to 2^(n-1)/n.

1, 1, 1, 2, 3, 5, 9, 16, 28, 51, 93, 171, 315, 585, 1092, 2048, 3855, 7282, 13797, 26214, 49932, 95325, 182361, 349525, 671089, 1290555, 2485513, 4793490, 9256395, 17895697, 34636833, 67108864, 130150524, 252645135, 490853405, 954437177, 1857283155, 3616814565

Offset: 1

Author

N. J. A. Sloane, Apr 17 2000

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A006788, A000048.

Programs

Magma

[Floor(2^(n-1)/n + 1/2): n in [1..45]]; // Vincenzo Librandi, Jul 21 2011

Mathematica

Table[Floor[2^(n-1)/n + 1/2], {n,40}] (* Harvey P. Dale, Jul 20 2011 *)

Formula

a(n) = round(hypergeometric([-n/2+1/2, -n/2+1], [3/2], 1)). - Peter Luschny, Sep 18 2014