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 A051169 Smallest number m such that 2*m - p is composite for the first n primes p. 3
 3, 6, 15, 49, 49, 49, 49, 110, 154, 154, 278, 278, 278, 278, 496, 496, 496, 496, 496, 496, 1321, 1321, 1321, 1321, 1321, 1321, 2686, 2686, 2686, 2686, 2686, 2686, 2686, 3713, 3713, 3713, 3713, 3713, 3713, 21766, 21766, 21766, 21766, 21766, 21766, 21766 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Computed by Peter G. Anderson at the Rochester Institute of Technology. LINKS Paul S. Bruckman and T. D. Noe, Table of n, a(n) for n=1..974 EXAMPLE a(2) = 6 because 2*6-2 = 10 and 2*6-3 = 9 are composite. MATHEMATICA a[n_] := a[n] = Catch[For[m = 2, True, m++, If[And @@ (! PrimeQ[2*m - #] &) /@ Prime /@ Range[n], Throw[m]]]]; Table[ Print[a[n]]; a[n], {n, 1, 46}] (* Jean-François Alcover, Jul 17 2012 *) Module[{nn=50, prs}, prs=Prime[Range[nn]]; Table[SelectFirst[Range[50000], AllTrue[Table[2#-p, {p, Take[prs, n]}], CompositeQ]&], {n, nn}]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 18 2015 *) PROG (Haskell) a051169 n = head [m | m <- [2..],             all (== 0) \$ map (a010051' . (2*m -)) \$ take n a000040_list] -- Reinhard Zumkeller, Apr 09 2015 CROSSREFS See A051610 and A116111 for records. Cf. A025017. Cf. A010051, A000040. Sequence in context: A028401 A005655 A277063 * A051610 A230950 A267552 Adjacent sequences:  A051166 A051167 A051168 * A051170 A051171 A051172 KEYWORD nice,nonn AUTHOR Paul S. Bruckman (pbruckman(AT)hotmail.com) EXTENSIONS More terms from Paul S. Bruckman, Jan 20 2007 Edited by N. J. A. Sloane, Apr 14 2007, May 04 2007, Jun 10 2008 STATUS approved

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Last modified October 17 07:57 EDT 2018. Contains 316276 sequences. (Running on oeis4.)