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A064712 Numbers n such that n^2 - prime(n) is a prime. 9
6, 10, 12, 18, 24, 28, 30, 40, 42, 48, 60, 76, 96, 104, 108, 114, 138, 146, 160, 166, 174, 176, 186, 190, 196, 198, 208, 230, 250, 258, 262, 270, 292, 296, 318, 320, 334, 336, 348, 356, 358, 362, 370, 372, 376, 382, 400, 420, 444, 454, 462, 472, 488, 494, 504 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A073497(a(n)) is a prime. - Zak Seidov, Apr 11 2011

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000

EXAMPLE

6 is in the sequence because 6^2 - Prime(6) = 36 - 13 = 23 is a prime.

MATHEMATICA

Select[ Range[ 6, 1000, 2 ], PrimeQ[ #^2 - Prime[ # ] ] & ]

PROG

(PARI) n=0; forstep (m=6, 10^9, 2, if (isprime(m^2 - prime(m)), write("b064712.txt", n++, " ", m); if (n==1000, break)) ) \\ Harry J. Smith, Sep 23 2009

(MAGMA) [n: n in [6..1000] | IsPrime(n^2-NthPrime(n))]; // Vincenzo Librandi, Apr 14 2011

CROSSREFS

Sequence in context: A315131 A046288 A076763 * A284667 A315132 A315133

Adjacent sequences:  A064709 A064710 A064711 * A064713 A064714 A064715

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Oct 13 2001

STATUS

approved

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Last modified May 28 12:26 EDT 2020. Contains 334681 sequences. (Running on oeis4.)