A151819 First component x of pairs (x,y) where x!+y! is a square, sorted on x.

0, 0, 0, 1, 1, 1, 2, 4, 4, 4

Offset

1,7

Comments

Conjecture: the only solutions for x!+y!=n^2 are x=0,0,0,1,1,1,2,4,4,4 and y=4,5,7,4,5,7,2,0,1,5 respectively.

Links

Table of n, a(n) for n=1..10.

Crossrefs

Added as a companion to A082871.

Sequence in context: A131118 A140765 A097541 * A079560 A330601 A088680

Adjacent sequences: A151816 A151817 A151818 * A151820 A151821 A151822

Keyword

nonn

Author

Farideh Firoozbakht, Jul 07 2009

Status

approved