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A063793 a(n) = Min{ q prime | nextprime(q) - q - 1 = prime(n)}, or 0 if none exist. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

Conjecture: a(n) > 0 for n > 1.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 2..217

FORMULA

a(n) = A000230((prime(n)+1)/2). - Charles R Greathouse IV, Apr 30 2015

EXAMPLE

The 3rd odd prime is 7 = 97 - 89 - 1 and for all p < 89 nextprime(p) - p <> 8; therefore a(3) = 89.

PROG

(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

CROSSREFS

Cf. A046933.

Sequence in context: A322269 A303890 A003540 * A217233 A316734 A096327

Adjacent sequences:  A063790 A063791 A063792 * A063794 A063795 A063796

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Aug 18 2001

EXTENSIONS

Offset changed by Charles R Greathouse IV, Apr 30 2015

a(26)-a(37) from Charles R Greathouse IV, Apr 30 2015

STATUS

approved

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Last modified September 28 10:48 EDT 2021. Contains 347714 sequences. (Running on oeis4.)