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A082871
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First component x of pairs (x,y) where x <= y and x!+y! is a square, sorted on x.
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1
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OFFSET
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1,8
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COMMENTS
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Conjecture: the only solutions for x!+y!=n^2 (x <= y) are x=0,0,0,1,1,1,2,4 and y=4,5,7,4,5,7,2,5 respectively.
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LINKS
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PROG
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(PARI) sumfactsq(n) = { for(x=0, n, for(y=1, n, z = x!+y!; if(issquare(z), print1(x" ")) ) ) }
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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