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 A217620 Primes of the form 2*n^2 + 82*n + 39. 9
 211, 499, 823, 1579, 2011, 4099, 6043, 6763, 8311, 10903, 11839, 18211, 27283, 28723, 34843, 38119, 41539, 56659, 58711, 76423, 86143, 88663, 93811, 99103, 110119, 121711, 124699, 130783, 149899, 163363, 173839, 181003, 188311, 222979, 227011, 231079, 247711 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Conjecture: 2^a(n)-1 is not prime; in other words, these primes are included in A054723. 2*a(n) + 1603 is a square. - Vincenzo Librandi, Apr 09 2015 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..3000 MATHEMATICA Select[Table[2 n^2 + 82 n + 39, {n, 600}], PrimeQ] PROG (Magma) [a: n in [1..600] | IsPrime(a) where a is 2*n^2+82*n+39]; CROSSREFS Cf. Primes of the form 2*n^2+2*(2*k+3)*n+(2*k+1): A176549 (k=0), A154577 (k=2), A154592 (k=3), A154601 (k=4), A217494 (k=7), A217495 (k=10), A217496 (k=11), A217497 (k=12), A217498 (k=13), A217499 (k=16), A217500 (k=17), A217501 (k=18), this sequence (k=19), A217621 (k=21). Cf. A054723. Subsequence of A002145. Sequence in context: A258332 A073102 A076167 * A289993 A300334 A032659 Adjacent sequences: A217617 A217618 A217619 * A217621 A217622 A217623 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Oct 09 2012 STATUS approved

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Last modified April 1 08:54 EDT 2023. Contains 361681 sequences. (Running on oeis4.)