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A154650
Primes p such that 4*p^2-8*p-9 is a prime.
2
3, 7, 13, 19, 37, 43, 61, 103, 109, 139, 181, 223, 229, 241, 307, 367, 397, 409, 433, 457, 463, 577, 631, 661, 727, 751, 811, 823, 829, 853, 919, 1009, 1063, 1087, 1117, 1213, 1231, 1279, 1291, 1321, 1423, 1429, 1471, 1597, 1609, 1699, 1741, 1753, 1783, 1789
OFFSET
1,1
LINKS
MAPLE
a := proc (n) if isprime(n) = true and isprime(4*n^2-8*n-9) = true then n else end if end proc: seq(a(n), n = 1 .. 2000); # Emeric Deutsch, Jan 27 2009
MATHEMATICA
Select[Prime[Range[200]], PrimeQ[4 #^2 - 8 # - 9] &] (* Vincenzo Librandi, Oct 15 2012 *)
PROG
(Magma) [p: p in PrimesInInterval(2, 2000) | IsPrime(4*p^2 - 8*p - 9) ]; // Vincenzo Librandi, Oct 15 2012
CROSSREFS
Cf. A154648.
Sequence in context: A048977 A216518 A342822 * A015913 A023200 A046136
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Jan 18 2009
EXTENSIONS
Extended by Emeric Deutsch, Jan 27 2009
STATUS
approved