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
KEYWORD
nonn
AUTHOR
STATUS
approved