OFFSET
1,2
COMMENTS
a(p) = p(p-1) if p is a prime.
a(p^k) = p (p^k - 1) if p is a prime and k >= 1. - Robert Israel, May 21 2015
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..1000
MAPLE
A:= n -> select(t->igcd(t, n)>1, [$1..n^2])[n-1]:
1, seq(A(n), n=2..100); # Robert Israel, May 21 2015
MATHEMATICA
Table[Join[{1}, Select[Range[n^2], GCD[n, #] > 1 &, n - 1]][[-1]], {n, 1, 60}](* Ivan Neretin, May 21 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Mar 27 2003
EXTENSIONS
More terms from Ryan Propper, Nov 05 2005
STATUS
approved