OFFSET
1,1
LINKS
Donovan Johnson, Table of n, a(n) for n = 1..1000
Max Alekseyev, PARI/GP Scripts for Miscellaneous Math Problems (invphi.gp).
EXAMPLE
invphi(65536*103) = {6750209,13500418}, so a(27) = 2.
Observe that a(15) = 0 because 47 needs very large 2^i multiplier (instead of 65536) to give nonempty InvPhi set.
MAPLE
[seq(nops(invphi(65536*ithprime(i))), i=1..128)];
PROG
(PARI) a(n) = invphiNum(65536 * prime(n)); \\ Amiram Eldar, Nov 11 2024, using Max Alekseyev's invphi.gp
CROSSREFS
KEYWORD
nonn,changed
AUTHOR
Labos Elemer, May 30 2002
STATUS
approved