A018048 Powers of fourth root of 2 rounded down.

1, 1, 1, 1, 2, 2, 2, 3, 4, 4, 5, 6, 8, 9, 11, 13, 16, 19, 22, 26, 32, 38, 45, 53, 64, 76, 90, 107, 128, 152, 181, 215, 256, 304, 362, 430, 512, 608, 724, 861, 1024, 1217, 1448, 1722, 2048, 2435, 2896, 3444, 4096, 4870, 5792, 6888, 8192, 9741, 11585, 13777, 16384

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Matthew House, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A017910, A017979, A018117.

Programs

Maple

seq(floor(2^(n/4)),n=0..100); #  Robert Israel, Jul 28 2015

Mathematica

a[n_] := Floor[2^(n/4)]; Array[a, 100, 0] (* Amiram Eldar, Apr 04 2025 *)

PARI

vector(70, n, n--; floor(2^(n/4))) \\ Michel Marcus, Jul 28 2015

PARI

a(n)=sqrtnint(2^n,4) \\ Charles R Greathouse IV, Jul 28 2015