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A155703 Primes p such that 2*p^2 + 16*p + 23 is also prime. 2
3, 7, 13, 19, 31, 43, 97, 127, 223, 241, 271, 283, 307, 397, 421, 439, 577, 601, 619, 661, 673, 691, 727, 853, 859, 967, 1009, 1051, 1063, 1123, 1153, 1237, 1321, 1429, 1447, 1543, 1567, 1597, 1609, 1657, 1669, 1861, 1867, 1933, 1951, 1987, 2017, 2089, 2203 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Prime[Range[2500]], PrimeQ[(2*#^2 + 16*# + 23)]&] (* Vincenzo Librandi, Oct 30 2012 *)

PROG

(MAGMA) [p: p in PrimesUpTo(3000)|IsPrime(2*p^2+16*p+23)]

CROSSREFS

Cf. A155702, A153037.

Sequence in context: A103966 A023237 A106061 * A023217 A106077 A216515

Adjacent sequences:  A155700 A155701 A155702 * A155704 A155705 A155706

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Jan 25 2009

EXTENSIONS

Entries confirmed by John W. Layman, Jun 17 2010.

STATUS

approved

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Last modified October 1 20:37 EDT 2014. Contains 247522 sequences.