

A082995


Distance from n!+1 to next larger square.


0



2, 1, 2, 0, 0, 8, 0, 80, 728, 224, 323, 39168, 82943, 176399, 215295, 3444735, 26167683, 114349224, 255004928, 1158920360, 11638526760, 42128246888, 191052974115, 97216010328, 2430400258224, 1553580508515, 4666092737475
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OFFSET

1,1


COMMENTS

The only known values of n such that n!+1 is a perfect square are 4, 5 and 7. Paul Leyland, et al. have found no other solutions for n <= 1 million (see link). For 1 <= n <= 11, n!+1 is within 1000 of being a square. Is there another n such that n!+1 <= "1000 away" from being a perfect square?


LINKS

Table of n, a(n) for n=1..27.
P. Leyland, Solutions to n!+1=m^2.


EXAMPLE

a(5)=0 because 5!+1 is a square. a(8)=80 because 8!+1 = 40321 and the next
larger square is 40401, so 4040140321 = 80.


CROSSREFS

Sequence in context: A317741 A317902 A317871 * A079549 A143374 A277899
Adjacent sequences: A082992 A082993 A082994 * A082996 A082997 A082998


KEYWORD

nonn


AUTHOR

Jason Earls, May 29 2003


STATUS

approved



