OFFSET
1,1
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..500
FORMULA
a(n) = A053287(3*n). - Max Alekseyev, Jan 09 2024
MATHEMATICA
EulerPhi[8^Range[30] - 1]
PROG
(PARI) {a(n) = eulerphi(8^n-1)}
(Python)
from sympy import totient
def A366654(n): return totient((1<<3*n)-1) # Chai Wah Wu, Oct 15 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Sean A. Irvine, Oct 15 2023
STATUS
approved