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 A243889 Primes of the form 2*n^2+30*n+13. 2
 661, 1201, 2281, 2713, 3181, 4801, 5413, 8221, 9013, 12541, 13513, 17761, 18913, 20101, 32413, 33961, 38821, 51421, 72481, 91921, 94513, 108013, 110821, 134581, 137713, 153913, 167521, 211801, 223681, 265621, 274441, 335281, 345181, 365413, 370561, 440761, 560641 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A142104. Conjecture: except 2281, 2^a(n)-1 is not prime; in other words, these primes are included in A054723. 2*a(n) + 199 is a square. - Vincenzo Librandi, Apr 10 2015 LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1000 MATHEMATICA Select[Table[2 n^2 + 30 n + 13, {n, 1000}], PrimeQ] PROG (Magma) [a: n in [1..800] | IsPrime(a) where a is 2*n^2+30*n+13]; CROSSREFS Cf. A142104. Cf. similar sequences listed in A243888. Sequence in context: A171394 A243886 A145750 * A105978 A208180 A317396 Adjacent sequences: A243886 A243887 A243888 * A243890 A243891 A243892 KEYWORD nonn,easy AUTHOR Vincenzo Librandi, Jun 16 2014 STATUS approved

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Last modified June 8 13:50 EDT 2023. Contains 363165 sequences. (Running on oeis4.)