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 A189118 a(n) = smallest composite (odd) number greater than a(n-1) such that a(n)+2n is the first prime after a(n). 2
 9, 25, 91, 119, 201, 295, 527, 891, 1133, 1341, 1671, 2479, 2973, 4299, 5593, 8469, 9553, 15691, 16145, 19621, 25481, 28233, 31423, 31909, 34073, 35619, 43337, 44295, 89695, 107381, 134519, 155943, 173363, 175143, 188037, 212705, 265629 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS More precise definition from Don Reble, Jul 29 2014. (Old definition was: Smallest composite odd number of first sequence of n consecutive composite odd numbers.) LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..70 EXAMPLE 9 is composite but 11 is not; 25 and 27 are composite but 29 is not; 91, 93, 95 are composite but 97 is not. MATHEMATICA imax=1000000; lst={}; q=1; Do[k=0; Do[If[PrimeQ[n], Break[], k++], {n, m, imax+200, 2}]; If[k==q, q++; AppendTo[lst, m]], {m, 5, imax, 2}]; lst CROSSREFS Cf. A002808, A071904, A161945, A075067. Sequence in context: A269662 A147428 A147436 * A075067 A075064 A147332 Adjacent sequences: A189115 A189116 A189117 * A189119 A189120 A189121 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Apr 16 2011 EXTENSIONS Definition revised by N. J. A. Sloane, Jul 29 2014 at the suggestion of Don Reble. STATUS approved

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Last modified August 10 00:01 EDT 2024. Contains 375044 sequences. (Running on oeis4.)