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A018064
Powers of fourth root of 7 rounded to nearest integer.
1
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
OFFSET
0,2
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
CROSSREFS
Cf. A011005.
Sequence in context: A293544 A080074 A317767 * A226161 A188624 A327010
KEYWORD
nonn
STATUS
approved