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 A098014 A098013/2. 0
 2, 2, 2, 3, 3, 2, 2, 3, 3, 3, 2, 3, 2, 3, 2, 2, 2, 7, 2, 3, 5, 3, 3, 2, 3, 3, 5, 2, 2, 2, 3, 5, 3, 3, 3, 3, 2, 5, 7, 2, 2, 7, 3, 5, 2, 3, 3, 3, 2, 3, 2, 5, 5, 3, 2, 3, 2, 2, 2, 2, 3, 3, 5, 3, 3, 3, 5, 3, 3, 3, 3, 2, 5, 2, 3, 3, 2, 3, 5, 5, 3, 3, 2, 3, 2, 2, 7, 5, 5, 2, 5, 7, 2, 2, 7, 2, 2, 2, 5, 2, 3, 3, 7, 2, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Half the difference between consecutive primes is prime. (1/2)(29 - 23) = 3, the 4th entry in the table. LINKS Table of n, a(n) for n=1..105. MATHEMATICA Select[Differences[Prime[Range[250]]]/2, PrimeQ] (* Harvey P. Dale, Dec 20 2012 *) PROG (PARI) f(n) = for(x=1, n, y=prime(x+1)-prime(x); if(isprime(y\2), print1(y\2", "))) (Magma) [ a: n in [1..2500] | IsPrime(a) where a is ((NthPrime(n+1)-NthPrime(n)) div 2 )]; // Vincenzo Librandi, Apr 19 2011 CROSSREFS Sequence in context: A348470 A317369 A096916 * A059957 A361088 A165924 Adjacent sequences: A098011 A098012 A098013 * A098015 A098016 A098017 KEYWORD easy,nonn AUTHOR Cino Hilliard, Sep 09 2004 STATUS approved

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Last modified August 12 19:26 EDT 2024. Contains 375113 sequences. (Running on oeis4.)