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A064361 Numbers k such that prime(k)^2 + k is prime. 2
1, 2, 4, 12, 18, 22, 30, 42, 52, 82, 84, 126, 142, 174, 178, 180, 186, 192, 198, 216, 220, 240, 252, 262, 298, 316, 348, 382, 400, 406, 412, 438, 478, 480, 492, 520, 522, 532, 546, 576, 604, 610, 630, 700, 730, 744, 784, 790, 832, 840, 852, 862, 904, 916, 940 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

MATHEMATICA

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

PROG

(PARI) j=[]; for(n=1, 1500, if(isprime(prime(n)^2+n), j=concat(j, n))); j

(PARI) { n=0; for (m=1, 10^9, if (isprime(prime(m)^2 + m), write("b064361.txt", n++, " ", m); if (n==1000, break)) ) } \\ Harry J. Smith, Sep 12 2009

CROSSREFS

Sequence in context: A085931 A125885 A067929 * A303403 A064407 A198392

Adjacent sequences:  A064358 A064359 A064360 * A064362 A064363 A064364

KEYWORD

easy,nonn

AUTHOR

Jason Earls, Sep 26 2001

STATUS

approved

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Last modified April 25 00:29 EDT 2019. Contains 322446 sequences. (Running on oeis4.)