OFFSET
1,1
COMMENTS
Each of the numbers 2^k*a(n), where k >= 1, is a noncototient.
LINKS
J. Browkin and A. Schinzel, On integers not of the form n - phi(n), Colloq. Math. 68 (1995), pp. 55-58.
A. Flammenkamp and F. Luca, Infinite families of noncototients, Colloq. Math. 86 (2000), pp. 37-41.
CROSSREFS
KEYWORD
nonn
AUTHOR
Arkadiusz Wesolowski, Oct 30 2015
STATUS
approved