OFFSET
1,1
LINKS
Max Alekseyev, Table of n, a(n) for n = 1..352
Eric W. Weisstein, MathWorld: Totient Function
Wikipedia, Euler's totient function
FORMULA
a(n) = n*A295497(n).
MATHEMATICA
Array[ EulerPhi[10^# - 1] &, 20] (* Robert G. Wilson v, Nov 22 2017 *)
PROG
(PARI) {a(n) = eulerphi(10^n-1)}
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Nov 22 2017
STATUS
approved