A018064 Powers of fourth root of 7 rounded to nearest integer.

1, 2, 3, 4, 7, 11, 19, 30, 49, 80, 130, 211, 343, 558, 907, 1476, 2401, 3905, 6352, 10333, 16807, 27338, 44467, 72329, 117649, 191365, 311270, 506304, 823543, 1339556, 2178890, 3544131, 5764801, 9376890, 15252230, 24808920, 40353607, 65638231

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..2000

Crossrefs

Cf. A011005.

Programs

Magma

R := RealField(20); r := R!7^(1/4); vals := [Round(r^i) : i in [0..40]]; print vals; // Vincenzo Librandi, May 31 2025

Mathematica

Round[(Power[7, (4)^-1])^Range[0,40]]  (* Harvey P. Dale, Jan 16 2011 *)

Python

from sympy import integer_nthroot
def A018064(n): return -integer_nthroot(m:=7**n, 4)[0]+integer_nthroot(m<<4, 4)[0] # Chai Wah Wu, Jun 20 2024