OFFSET
1
LINKS
FORMULA
EXAMPLE
For n = 121, phi(121) = 110 = 2*5*11, while 120 = 2^3 * 3 * 5, thus as the exponent of 2 in 110 is <= the exponent in 120, a(121) = 1.
PROG
(PARI) A353498(n) = ((n>1)&&(valuation(eulerphi(n), 2)<=valuation(n-1, 2)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Apr 22 2022
STATUS
approved