A018136 Powers of fifth root of 8 rounded to nearest integer.

1, 2, 2, 3, 5, 8, 12, 18, 28, 42, 64, 97, 147, 223, 338, 512, 776, 1176, 1783, 2702, 4096, 6208, 9410, 14263, 21619, 32768, 49667, 75281, 114105, 172951, 262144, 397336, 602249, 912838, 1383604, 2097152

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Paolo Xausa, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A011093.

Programs

Mathematica

Round[(8^(1/5))^Range[0, 50]] (* Paolo Xausa, Jul 01 2024 *)

Python

from gmpy2 import iroot_rem
def A018136(n):
    i, j = iroot_rem(1<<3*n,5)
    return int(i)+int(j<<5>=10*i*((i*((i*(i+1)<<1)+1)<<2)+1)+1) # Chai Wah Wu, Jun 20 2024