OFFSET
2,1
LINKS
Seiichi Manyama, Table of n, a(n) for n = 2..1000
Eric Weisstein's World of Mathematics, Totient Function.
Wikipedia, Euler's totient function.
MATHEMATICA
EulerPhi[Range[2, 50]^3 - 1]/3 (* Paolo Xausa, Jun 18 2024 *)
PROG
(PARI) {a(n) = eulerphi(n^3-1)/3}
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 13 2018
STATUS
approved