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 A051634 Strong primes: prime(n) > (prime(n-1) + prime(n+1))/2. 34
 11, 17, 29, 37, 41, 59, 67, 71, 79, 97, 101, 107, 127, 137, 149, 163, 179, 191, 197, 223, 227, 239, 251, 269, 277, 281, 307, 311, 331, 347, 367, 379, 397, 419, 431, 439, 457, 461, 479, 487, 499, 521, 541, 557, 569, 587, 599 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Prime(n) such that prime(n)-prime(n-1) > prime(n+1)-prime(n). - Juri-Stepan Gerasimov, Jan 01 2011 a(n) > A051635(n). - Thomas Ordowski, Jul 25 2012 REFERENCES A. Murthy, Smarandache Notions Journal, Vol. 11 N. 1-2-3 Spring 2000. LINKS T. D. Noe, Table of n, a(n) for n = 1..1000 EXAMPLE 11 belongs to the sequence because 11 > (7 + 13)/2. MATHEMATICA Transpose[Select[Partition[Prime[Range[10^2]], 3, 1], #[[2]]>(#[[1]]+#[[3]])/2 &]][[2]] (* Vladimir Joseph Stephan Orlovsky, May 01 2008 *) p=Prime[Range[200]]; p[[Flatten[1+Position[Sign[Differences[p, 2]], -1]]]] PROG (PARI) p=2; q=3; forprime(r=5, 1e4, if(2*q>p+r, print1(q", ")); p=q; q=r) \\ Charles R Greathouse IV, Jul 19 2011 (Haskell) a051634 n = a051634_list !! (n-1) a051634_list = f a000040_list where    f (p:qs@(q:r:ps)) = if 2 * q > (p + r) then q : f qs else f qs -- Reinhard Zumkeller, May 09 2013 CROSSREFS Cf. A006562, A051635, A229832. Subsequence of A178943; A225493 (multiplicative closure). Sequence in context: A240095 A105886 A225493 * A038918 A220293 A166307 Adjacent sequences:  A051631 A051632 A051633 * A051635 A051636 A051637 KEYWORD nice,nonn AUTHOR Felice Russo, Nov 15 1999 STATUS approved

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Last modified November 18 21:04 EST 2018. Contains 317331 sequences. (Running on oeis4.)