A060505 a(n) = floor(2^n/(n^2)).

2, 1, 0, 1, 1, 1, 2, 4, 6, 10, 16, 28, 48, 83, 145, 256, 453, 809, 1452, 2621, 4755, 8665, 15857, 29127, 53687, 99273, 184112, 342392, 638372, 1193046, 2234634, 4194304, 7887910, 14861478, 28048766, 53024287, 100393684, 190358661, 361443664

Offset: 1

Author

Labos Elemer, Apr 11 2001

Keywords

• easy
• nonn

Links

• Harry J. Smith, Table of n, a(n) for n = 1..200

Programs

Mathematica

Table[Floor[2^w/(w^2)], {w, 1, 40}];

PARI

a(n)={floor(2^n/(n^2))} \\ Harry J. Smith, Jul 06 2009

Formula

a(n) = floor(A000079(n)/A000290(n+1)).