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A160681 Primes of form 10 * 2^(2^n) + 19. 0

%I

%S 59,179,2579,655379,42949672979,184467440737095516179,

%T 3402823669209384634633746074317682114579

%N Primes of form 10 * 2^(2^n) + 19.

%C Primes of the form 10*A000215(n) + 9. - _Arkadiusz Wesolowski_, Mar 04 2011

%C a(n) is composite for n = 0 and all 8 <= n <= 26. - _Arkadiusz Wesolowski_, Oct 21 2013

%H G. L. Honaker, Jr. and Chris Caldwell, <a href="http://primes.utm.edu/curios/cpage/18595.html">Prime Curios! 9</a>

%t Select[Table[10*2^2^n + 19, {n, 0, 7}], PrimeQ] (* _Arkadiusz Wesolowski_, Mar 04 2011 *)

%o (MAGMA) [10*2^2^n+19 : n in [0..7] | IsPrime(10*2^2^n+19)]; // _Arkadiusz Wesolowski_, Mar 04 2011

%o (PARI) for(n=0, 7, if(isprime(x=(10*2^2^n+19)), print1(x, ", "))); \\ _Arkadiusz Wesolowski_, Mar 04 2011

%Y Cf. A030433, A000215.

%K nonn,hard

%O 1,1

%A _Arkadiusz Wesolowski_, May 23 2009

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Last modified November 27 12:51 EST 2021. Contains 349394 sequences. (Running on oeis4.)