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 A002373 Smallest prime in decomposition of 2n into sum of two odd primes. (Formerly M2273 N0899) 31
 3, 3, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 7, 3, 3, 5, 7, 3, 5, 3, 3, 5, 3, 5, 7, 3, 5, 7, 3, 3, 5, 7, 3, 5, 3, 3, 5, 7, 3, 5, 3, 5, 7, 3, 5, 7, 19, 3, 5, 3, 3, 5, 3, 3, 5, 3, 5, 7, 13, 11, 13, 19, 3, 5, 3, 5, 7, 3, 3, 5, 7, 11, 11, 3, 3, 5, 7, 3, 5, 7, 3, 5, 3, 5, 7, 3, 5, 7, 3, 3, 5, 7, 11, 11, 3, 3, 5, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,1 COMMENTS See A020481 for another version. a(A208662(n)) = A065091(n) and a(m) <> A065091(n) for m < A208662(n). - Reinhard Zumkeller, Feb 29 2012 Records are in A025019, their indices in A051610. - Ralf Stephan, Dec 29 2013 Note that these primes do not all belong to a twin prime pair. The first instance is a(110) = 23. - Michel Marcus, Aug 17 2020 from a suggestion by Pierre CAMI REFERENCES D. H. Lehmer, Guide to Tables in the Theory of Numbers. Bulletin No. 105, National Research Council, Washington, DC, 1941, p. 80. N. Pipping, Neue Tafeln für das Goldbachsche Gesetz nebst Berichtigungen zu den Haussnerschen Tafeln, Finska Vetenskaps-Societeten, Comment. Physico Math. 4 (No. 4, 1927), pp. 1-27. N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS T. D. Noe, Table of n, a(n) for n = 3..10000 Eric Weisstein's World of Mathematics, Goldbach Partition Wikipedia, Goldbach's conjecture MATHEMATICA Table[k = 2; While[q = Prime[k]; ! PrimeQ[2*n - q], k++]; q, {n, 3, 100}] (* Jean-François Alcover, Apr 26 2011 *) Table[Min[Flatten[Select[IntegerPartitions[2*n, {2}], AllTrue[ #, OddQ] && AllTrue[#, PrimeQ]&]]], {n, 3, 100}] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 31 2020 *) PROG (Haskell) a002373 n = head \$ dropWhile ((== 0) . a010051 . (2*n -)) a065091_list -- Reinhard Zumkeller, Feb 29 2012 (PARI) a(n)=forprime(p=3, n, if(isprime(2*n-p), return(p))) \\ Charles R Greathouse IV, May 18 2015 CROSSREFS Cf. A002372, A002374, A014092, A065091, A010051. Sequence in context: A301738 A302387 A049613 * A236569 A103153 A162022 Adjacent sequences:  A002370 A002371 A002372 * A002374 A002375 A002376 KEYWORD nonn,nice,easy AUTHOR EXTENSIONS More terms from Ray Chandler, Sep 19 2003 STATUS approved

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Last modified September 28 17:43 EDT 2020. Contains 337393 sequences. (Running on oeis4.)