login
A093486
Least k >= 0 such that k! + n is a square, or -1 if no such number exists.
0
0, 4, 2, 0, -1, -1, -1, 2, 0, 6, 3, -1, 4, -1, 2, 0, -1, -1, -1, 3, -1, -1, -1, 2, 0, 4, -1, -1, -1, -1, 3, -1, -1, -1, 2, 0, -1, -1, -1, -1, 4, -1, -1, 3, -1, -1, -1, 2, 0, 5, -1, -1, -1, -1, -1, -1, -1, 4, 3, -1, -1, -1, 2, 0, 6, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 3, 4, -1, -1, 2, 0, 8, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 3, -1
OFFSET
1,2
COMMENTS
It is only a guess that a(4)=a(5)=a(6) = -1.
All -1 values are unproved. I have checked all k <= 2000. - David Wasserman, Apr 06 2007
CROSSREFS
Sequence in context: A107088 A137986 A330768 * A259618 A377036 A354681
KEYWORD
less,sign
AUTHOR
Amarnath Murthy, Apr 14 2004
EXTENSIONS
More terms from David Wasserman, Apr 06 2007
STATUS
approved