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[Mohammed BOUAYOUN]

Dear SeqFan,

Let a(n) = n!.2^n +1
a(n) is prime for n=1 and n=259 but there are no other prime for n<2650
Can any one extend this sequence ?
 I remark that if p is prime then p divide a(p-1)

we can prove this by wilson's theorem and Fermat's Little Theorem

if p is prime and gcd(q,p)=1 then p divide (p-1)!.q^(p-1)  + 1


Thanks

M.Bouayoun
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