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A130286 Strongly-single primes: primes p such that neither previousprime(p) nor nextprime(p) is a twin prime. 1
83, 89, 127, 163, 167, 257, 331, 359, 367, 373, 379, 383, 389, 397, 401, 443, 449, 479, 487, 491, 499, 503, 547, 557, 587, 677, 683, 691, 701, 709, 719, 727, 733, 739, 743, 751, 757, 761, 769, 773, 787, 907, 911, 919, 929, 937, 941, 947, 953, 967, 971, 977 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Cf. A007510 Single (or isolated or non-twin) primes. See also A000040 The prime numbers, A001097 Twin primes, A071904 Odd composite numbers.

MATHEMATICA

PrimeNext[n_]:=Module[{k}, k=n+1; While[ !PrimeQ[k], k++ ]; k]; PrimePrev[n_]:=Module[{k}, k=n-1; While[ !PrimeQ[k], k-- ]; k]; lst={}; Do[p=Prime[n]; If[ !PrimeQ[p-2]&&!PrimeQ[PrimePrev[p]-2]&&!PrimeQ[p+2]&&!PrimeQ[PrimeNext[p]+2], AppendTo[lst, p]], {n, 6!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jul 21 2009]

CROSSREFS

Cf. A000040, A001097, A007510, A071904.

Sequence in context: A106418 A031961 A108751 * A062677 A045714 A090156

Adjacent sequences:  A130283 A130284 A130285 * A130287 A130288 A130289

KEYWORD

nonn

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Aug 06 2007

EXTENSIONS

Added mathematica, edited some terms Vladimir Orlovsky (4vladimir(AT)gmail.com), Jul 21 2009

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Last modified February 14 08:58 EST 2012. Contains 205614 sequences.