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

0,2

Links

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

Mathematica

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

Prog

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

Crossrefs

Cf. A011005.

Sequence in context: A293544 A080074 A317767 * A226161 A188624 A327010

Adjacent sequences: A018061 A018062 A018063 * A018065 A018066 A018067

Keyword

nonn

Author

N. J. A. Sloane

Status

approved