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A063793
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a(n) = Min{ q prime | nextprime(q) - q - 1 = prime(n)}, or 0 if none exist.
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1
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7, 23, 89, 199, 113, 523, 887, 1669, 4297, 5591, 30593, 16141, 15683, 28229, 35617, 43331, 34061, 134513, 31397, 404597, 542603, 461717, 404851, 604073, 1444309, 1388483, 2238823, 1468277, 492113, 3851459, 1357201, 3826019, 7621259, 13626257, 8421251, 49269581
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OFFSET
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2,1
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COMMENTS
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Conjecture: a(n) > 0 for n > 1.
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LINKS
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FORMULA
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EXAMPLE
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The 3rd odd prime is 7 = 97 - 89 - 1 and for all p < 89 nextprime(p) - p <> 8; therefore a(3) = 89.
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PROG
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(PARI) a(n)=my(t=prime(n)+1, p=2); forprime(q=3, , if(q-p==t, return(p)); p=q) \\ Charles R Greathouse IV, Apr 30 2015
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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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