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A077800 List of twin primes {p, p+2}. 39
3, 5, 5, 7, 11, 13, 17, 19, 29, 31, 41, 43, 59, 61, 71, 73, 101, 103, 107, 109, 137, 139, 149, 151, 179, 181, 191, 193, 197, 199, 227, 229, 239, 241, 269, 271, 281, 283, 311, 313, 347, 349, 419, 421, 431, 433, 461, 463, 521, 523, 569, 571, 599, 601, 617, 619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Union (with repetition) of A001359 and A006512.

REFERENCES

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards Applied Math. Series 55, 1964 (and various reprintings), p. 870.

H. Tronnolone, A tale of two primes, COLAUMS Space, #3, 2013, http://maths.adelaide.edu.au/hayden.tronnolone/publications/A_tale_of_two_primes.pdf

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

J. P. Delahaye, Twin Primes:Enemy Brothers?

J. C. Evard, Twin primes and their applications

Wikipedia, Twin prime

Index entries for primes, gaps between

MATHEMATICA

Sort[ Join[ Select[ Prime[ Range[ 115]], PrimeQ[ # - 2] &], Select[ Prime[ Range[ 115]], PrimeQ[ # + 2] &]]] (from Robert G. Wilson v, Jun 09 2005)

Select[ Partition[ Prime@ Range@ 115, 2, 1], #[[1]] + 2 == #[[2]] &] // Flatten

Flatten[Select[{#, # + 2} & /@Prime[Range[1000]], PrimeQ[Last[#]]&]] (* Vincenzo Librandi, Nov 01 2012 *)

PROG

(Haskell)

a077800 n = a077800_list !! (n-1)

a077800_list = concat $ zipWith (\p q -> if p == q+2 then [q, p] else [])

                                (tail a000040_list) a000040_list

-- Reinhard Zumkeller, Nov 27 2011

(PARI) p=2; forprime(q=3, 1e3, if(q-p==2, print1(p", "q", ")); p=q) \\ Charles R Greathouse IV, Mar 22 2013

CROSSREFS

Cf. A070076, A095958. See A001097 for another version.

Sequence in context: A063202 A058020 A069201 * A118409 A162779 A158284

Adjacent sequences:  A077797 A077798 A077799 * A077801 A077802 A077803

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Dec 03, 2002

STATUS

approved

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Last modified October 21 00:03 EDT 2014. Contains 248371 sequences.