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Search: id:A118744
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| A118744 |
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Primes of the form n!! + n - 1. |
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+0
1
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| 3, 5, 11, 19, 53, 953, 46091, 34459441, 3715891219, 6332659870762850657, 107145471557284795514880041
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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n=2 2!! + 2 - 1 = 2 + 2 - 1 = 3
n=4 4!! + 4 - 1 = 4*2 + 4 - 1 = 11
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MAPLE
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SFACT:= proc(n) local i, j, k; for k from 1 by 1 to n do i:=k; j:=k-2; while j >0 do i:=i*j; j:=j-2; od: if isprime(i+k-1) then print(i+k-1); fi; od: end: SFACT(550);
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CROSSREFS
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Sequence in context: A045691 A045961 A117272 this_sequence A092672 A061068 A058932
Adjacent sequences: A118741 A118742 A118743 this_sequence A118745 A118746 A118747
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KEYWORD
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nonn
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AUTHOR
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Paolo P. Lava & Giorgio Balzarotti (ppl(AT)spl.at), May 22 2006
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