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 A260376 Values of n such that prime(prime(n)) + n is a prime number. 0
 2, 6, 16, 20, 30, 42, 78, 90, 92, 102, 108, 118, 124, 126, 128, 132, 136, 150, 160, 166, 180, 182, 186, 194, 196, 202, 206, 210, 214, 230, 270, 280, 294, 348, 356, 358, 366, 370, 374, 378, 418, 436, 456, 458, 472, 474, 478, 492, 522, 546, 556, 560, 570, 584, 586, 590 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Inspired by A061068. Obviously, sequence only can include even numbers. Initial primes of the form prime(prime(n)) + n are 7, 47, 257, 373, 647, 1129, 2797, 3389, 3499, 4129, 4447. LINKS EXAMPLE For n=2, prime(prime(2)) + 2 = prime(3) + 2 = 7. 7 is a prime number. MATHEMATICA Select[Range[600], PrimeQ[Prime[Prime[#]] + #] &] (* Vincenzo Librandi, Aug 30 2015 *) PROG (PARI) for(n=1, 1e3, if(isprime(prime(prime(n))+n), print1(n", "))) (MAGMA) [n: n in [1..600] | IsPrime(NthPrime(NthPrime(n))+n)]; // Vincenzo Librandi, Aug 30 2015 (Perl) use ntheory ":all"; my @p = grep { is_prime(nth_prime(nth_prime(\$_))+\$_) } 1..10000; say join ", ", @p; # Dana Jacobsen, Sep 02 2015 CROSSREFS Cf. A006450. Sequence in context: A080622 A082374 A085226 * A330866 A071522 A192532 Adjacent sequences:  A260373 A260374 A260375 * A260377 A260378 A260379 KEYWORD nonn,easy AUTHOR Altug Alkan, Aug 29 2015 STATUS approved

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Last modified August 15 16:02 EDT 2020. Contains 336505 sequences. (Running on oeis4.)