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 A089238 Numbers n such that 3*n^2/2 - 1 is a prime. 0
 2, 4, 6, 10, 14, 16, 20, 24, 26, 34, 40, 44, 54, 56, 60, 64, 70, 76, 86, 90, 104, 110, 116, 120, 124, 126, 130, 136, 140, 146, 150, 154, 164, 166, 174, 186, 194, 200, 204, 230, 240, 244, 260, 264, 286, 300, 306, 336, 346, 354, 374, 386, 394, 400, 414, 416, 420 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All terms must be even numbers. - Harvey P. Dale, Jul 03 2017 REFERENCES M. Cerasoli, F. Eugeni and M. Protasi, Elementi di Matematica Discreta, Bologna 1988 Emanuele Munarini and Norma Zagaglia Salvi, Matematica Discreta,UTET, CittaStudiEdizioni, Milano 1997 LINKS MATHEMATICA Select[Range[0, 500, 2], PrimeQ[(3#^2)/2-1]&] (* Harvey P. Dale, Jul 03 2017 *) PROG (PARI) forstep(n=2, 1000, 2, if(isprime(3*n^2/2-1), print1(n, ", "))) - Rick L. Shepherd, May 06 2008 CROSSREFS Cf. A090686. Sequence in context: A075574 A104692 A066755 * A005574 A109807 A259645 Adjacent sequences:  A089235 A089236 A089237 * A089239 A089240 A089241 KEYWORD nonn AUTHOR Giovanni Teofilatto, Dec 22 2003 EXTENSIONS Corrected and extended by Rick L. Shepherd, May 06 2008 STATUS approved

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Last modified November 29 23:37 EST 2020. Contains 338780 sequences. (Running on oeis4.)