editing
approved
Subsequence of A039770. A037896 is a subsequence.
reviewed
proposed
Sequences where phi(k) is a perfect power: A039770 (square), A039771 (cube), A078164 (4th, this sequence (4th), A078165 (5th), A078166 (6th), A078167 (7th), A078168 (8th), A078169 (9th), A078170 (10th).
Bernard Schott: Deleted autoreference A078164 in Xrefs.
Bernard Schott: Yes, ok, thanks.
AsA013776 is a subsequence since phi(2^(4*n+1)) = (2^n)^4, A013776 is a subsequence. - Bernard Schott, Sep 22 2022
Michel Marcus: ok ?
Subsequence of primes is A037896 sincèrementsince in this case : phi(k^4+1) = k^4. - Bernard Schott, Mar 05 2023
Bernard Schott: Comment for subsequence of primes.