login
A018133
Powers of fifth root of 7 rounded to nearest integer.
2
1, 1, 2, 3, 5, 7, 10, 15, 22, 33, 49, 72, 107, 157, 232, 343, 506, 747, 1102, 1627, 2401, 3543, 5229, 7717, 11389, 16807, 24803, 36604, 54019, 79720, 117649, 173623, 256229, 378135, 558042, 823543
OFFSET
0,3
MATHEMATICA
Round[Surd[7, 5]^Range[0, 40]] (* Harvey P. Dale, Jul 27 2021 *)
PROG
(Python)
from gmpy2 import iroot_rem
def A018133(n):
i, j = iroot_rem(7**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
CROSSREFS
Cf. A011092.
Sequence in context: A170877 A003410 A362757 * A261081 A116975 A286227
KEYWORD
nonn
AUTHOR
STATUS
approved