OFFSET
1,6
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
EXAMPLE
a(30) = 19 since 30k+m is always composite if m = 0, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 26, 27 or 28
MATHEMATICA
Table[n - EulerPhi[n] - PrimeNu[n], {n, 1, 100}] (* G. C. Greubel, May 13 2017 *)
PROG
(PARI) for(n=1, 100, print1(n - eulerphi(n) - omega(n), ", ")) \\ G. C. Greubel, May 13 2017
CROSSREFS
KEYWORD
nonn,look
AUTHOR
Henry Bottomley, Sep 08 2000
STATUS
approved