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A118813
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Primes of the form (2n)! - n! - 1.
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0
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OFFSET
| 1,1
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COMMENTS
| The next term is too large to include.
All the numbers end in 9.
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REFERENCES
| G. Balzarotti and P. P. Lava, Le sequenze di numeri interi, Hoepli, 2008, p. 159.
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EXAMPLE
| For n=5, (2*5)! - 5! - 1 = 3628800 - 120 - 1 = 3628679, which is prime.
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MAPLE
| PFACT:=proc(N) local i, r; for i from 1 by 1 to N do r:=(2*i)!-i!-1; if isprime(r) then print(i); fi; od; end: PFACT(100);
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CROSSREFS
| Sequence in context: A053078 A183970 A116221 * A127229 A068158 A011521
Adjacent sequences: A118810 A118811 A118812 * A118814 A118815 A118816
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KEYWORD
| nonn,changed
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AUTHOR
| Paolo P. Lava and Giorgio Balzarotti (paoloplava(AT)gmail.com), May 23 2006
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