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Search: id:A067362
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| A067362 |
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a(n) = p - n!^2, where p is the smallest prime > n!^2+1. |
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+0
6
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| 2, 3, 5, 11, 7, 11, 11, 13, 23, 17, 13, 59, 23, 31, 23, 41, 59, 67, 29, 31, 103, 389, 59, 107, 47, 127, 67, 181, 101, 97, 409, 37, 61, 43, 61, 47, 263, 109, 53, 199, 167, 337, 47, 131, 127, 73, 181, 257, 191, 101, 83, 79, 181, 167, 229, 859, 421, 433, 107, 971
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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The first 157 terms are primes. Are all terms prime? For n!^i, with 0<i<6, it looks like the terms are prime, too (see references). But for n!^6: a(28)=1189=29*41.
The first 200 terms are primes. - Jon Perry and Christ van Willegen, Mar 07 2003
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LINKS
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Cyril Banderier, Fortunate Numbers
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MATHEMATICA
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a[n_] := For[i=2, True, i++, If[PrimeQ[n!^2+i], Return[i]]]
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PROGRAM
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(MuPAD) for n from 1 to 50 do f := n!^2:a := nextprime(f+2)-f:print(a) end_for
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CROSSREFS
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Cf. A037153, A037153, A005235, A067363, A067364, A067365.
Sequence in context: A154956 A130165 A083397 this_sequence A131200 A101595 A084331
Adjacent sequences: A067359 A067360 A067361 this_sequence A067363 A067364 A067365
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KEYWORD
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nonn
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AUTHOR
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Frank Buss (fb(AT)frank-buss.de), Jan 19 2002
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EXTENSIONS
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Edited by Dean Hickerson (dean.hickerson(AT)yahoo.com), Mar 02 2002
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