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A227533 Smallest e > 1 such that (2n)^e is a totient, or 0 if no such e exists. 4
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 4, 2, 3, 2, 2, 2, 4, 2, 2, 2, 2, 2, 3, 2, 5, 2, 2, 2, 2, 2, 2, 3, 3, 2, 4, 2, 15, 2, 2, 4, 2, 2, 3, 2, 3, 2, 4, 2, 2, 2, 2, 2, 3, 2, 7, 2, 2, 2, 2, 2, 2, 2, 4, 2, 3, 2, 2, 2, 2, 3, 3, 2, 8, 2, 2, 4, 15, 2, 2, 3, 2, 2, 5, 2, 4, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Conjecture: a(n) > 0 for all n.
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..100000
EXAMPLE
a(1) = 2 because phi(5) = 2^2. a(11) = 3 because phi(13315) = 22^3 but phi(k) is not equal to 22^2 for any k.
PROG
(PARI) a(n)=my(k=2); while(!istotient((2*n)^k), k++); k
CROSSREFS
Sequence in context: A032550 A339172 A036450 * A235124 A235125 A238418
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)