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A154619 Primes of the form (4n^2+4n-5)/5. 0
23, 71, 167, 191, 479, 743, 1583, 2039, 2927, 3863, 5711, 6551, 7919, 9767, 10487, 11423, 15791, 16703, 18119, 21647, 21911, 24359, 27527, 32159, 35111, 35447, 38543, 43991, 45887, 46271, 52223, 54287, 55967, 60719, 67511, 69383, 76631 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

The n that generate integers of the form (4n^2+4n-5)/5 are in A047208. The primes are generated by the subset n = 5, 9, 14, 15, 24, 30, ... of these. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 25 2009

MAPLE

a := proc (n) if type((4/5)*n^2+(4/5)*n-1, integer) = true and isprime((4/5)*n^2+(4/5)*n-1) = true then (4/5)*n^2+(4/5)*n-1 else end if end proc: seq(a(n), n = 1 .. 340); [From Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 21 2009]

CROSSREFS

Cf. A028880

Sequence in context: A086104 A188831 A183012 * A142405 A139962 A139878

Adjacent sequences:  A154616 A154617 A154618 * A154620 A154621 A154622

KEYWORD

nonn

AUTHOR

Vincenzo Librandi (vincenzo.librandi(AT)tin.it), Jan 16 2009

EXTENSIONS

Definition corrected and more terms from R. J. Mathar and Omar E. Pol, Jan 24 2009

Extended by Emeric Deutsch (deutsch(AT)duke.poly.edu), Jan 21 2009

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Last modified February 17 21:13 EST 2012. Contains 206085 sequences.