OFFSET
1,2
COMMENTS
a(p) = p*(p-1) for all primes p. a(n^2) = 0 for all positive integers n.
LINKS
Ivan Neretin, Table of n, a(n) for n = 1..10000
MATHEMATICA
f[n_]:=Module[{m=First[Select[Divisors[n], #>=Sqrt[n]&]]}, m^2-n]; Array[f, 65] (* Harvey P. Dale, Apr 02 2011 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Leroy Quet, May 01 2008
EXTENSIONS
Extended by Ray Chandler, Jul 01 2009
STATUS
approved