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 A154632 Odd primes p such that (4*p^2-8*p-9)/3 is a prime. 1
 5, 17, 23, 41, 59, 71, 89, 149, 197, 233, 239, 347, 359, 401, 419, 449, 563, 683, 761, 773, 827, 887, 971, 977, 1049, 1061, 1097, 1193, 1277, 1373, 1439, 1553, 1571, 1787, 1871, 1877, 1931, 2069, 2267, 2273, 2381, 2417, 2447, 2687, 2699, 2777, 2843, 2957 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 EXAMPLE For p=5, (4*p^2-8*p-9)/3 = 17; for p=149, (4*p^2-8*p-9)/3 = 29201. MAPLE a := proc (n) if isprime(n) = true and type((4/3)*n^2-(8/3)*n-3, integer) = true and isprime((4/3)*n^2-(8/3)*n-3) = true then n else end if end proc: seq(a(n), n = 2 .. 4000); # Emeric Deutsch, Jan 20 2009 MATHEMATICA Select[Prime[Range[2, 500]], PrimeQ[(4 #^2 - 8 # - 9)/3] &] (* Harvey P. Dale, May 20 2012 *) CROSSREFS Cf. A154616. Subsequence of A007528. Sequence in context: A105884 A019410 A133423 * A236119 A141275 A303193 Adjacent sequences:  A154629 A154630 A154631 * A154633 A154634 A154635 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Jan 18 2009 EXTENSIONS Extended by Emeric Deutsch, Jan 20 2009 Formatting of definition clarified by Harvey P. Dale, May 20 2012 STATUS approved

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Last modified September 16 08:53 EDT 2019. Contains 327092 sequences. (Running on oeis4.)