OFFSET
-1,1
COMMENTS
Although Pi takes all values, solutions are not guaranteed since nontotient numbers exist.
EXAMPLE
n=-1: 6 solutions = {6,12,18,24,42,60}, a(-1)=6; n=5: for 6 terms of {11,32,34,50,70,150}, phi(#) - pi(#) = 6 holds, so a(5)=6; n=63: no solution was found at x <= 1000000.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 02 2002
STATUS
approved