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 A029707 Numbers n such that the n-th and the (n+1)-st primes are twin primes. 40
 2, 3, 5, 7, 10, 13, 17, 20, 26, 28, 33, 35, 41, 43, 45, 49, 52, 57, 60, 64, 69, 81, 83, 89, 98, 104, 109, 113, 116, 120, 140, 142, 144, 148, 152, 171, 173, 176, 178, 182, 190, 201, 206, 209, 212, 215, 225, 230, 234, 236, 253, 256, 262, 265, 268, 277 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers m such that prime(m)^2 == 1 mod (prime(m) + prime(m + 1)). - Zak Seidov, Sep 18 2013 LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..86027 FORMULA a(n) = A107770(n) - 1. - Juri-Stepan Gerasimov, Dec 16 2009 MAPLE A029707 := proc(n)     numtheory[pi](A001359(n)) ; end proc: seq(A029707(n), n=1..30); # R. J. Mathar, Feb 19 2017 MATHEMATICA Select[ Range@300, PrimeQ[ Prime@# + 2] &] (* Robert G. Wilson v, Mar 11 2007 *) Flatten[Position[Flatten[Differences/@Partition[Prime[Range[100]], 2, 1]], 2]](* Harvey P. Dale, Jun 05 2014 *) PROG (Sage) def A029707(n) :    a = [ ]    for i in (1..n) :       if (nth_prime(i+1)-nth_prime(i) == 2) :          a.append(i)    return(a) A029707(277) # Jani Melik, May 15 2014 CROSSREFS Cf. A014574, A027833 (first differences), A007508. Equals PrimePi(A001359) (cf. A000720). Sequence in context: A194238 A270192 A053034 * A175092 A265250 A090499 Adjacent sequences:  A029704 A029705 A029706 * A029708 A029709 A029710 KEYWORD nonn AUTHOR N. J. A. Sloane, Dec 11 1999 STATUS approved

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Last modified December 18 18:07 EST 2018. Contains 318243 sequences. (Running on oeis4.)