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A182048 Numbers n such that 16n^2-2n-1 and 16n^2+2n-1 are both primes. 1
1, 2, 3, 5, 6, 7, 10, 13, 19, 29, 32, 36, 62, 63, 70, 75, 78, 85, 93, 96, 102, 107, 109, 119, 123, 128, 145, 158, 164, 174, 177, 190, 192, 197, 219, 241, 247, 252, 280, 284, 299, 304, 318, 335, 340, 344, 354, 361, 374, 377, 382, 385, 387, 427, 434, 439, 440 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..3500

EXAMPLE

a(1)=1 because 16*1^2-2*1-1=13 is prime and 16*1^2+2*1-1=17 is prime.

MATHEMATICA

Select[Range[500], PrimeQ[16 #^2 - 2 # - 1] && PrimeQ[16 #^2 + 2 # - 1] &] (* T. D. Noe, Apr 16 2012 *)

Select[Range[500], AllTrue[16#^2-1+{2#, -2#}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Jan 01 2018 *)

CROSSREFS

Cf. A171748, A181981.

Sequence in context: A030051 A183071 A139826 * A028722 A030050 A018336

Adjacent sequences:  A182045 A182046 A182047 * A182049 A182050 A182051

KEYWORD

nonn

AUTHOR

Gerasimov Sergey, Apr 08 2012

EXTENSIONS

Corrected and extended by T. D. Noe, Apr 16 2012

STATUS

approved

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Last modified October 23 19:37 EDT 2019. Contains 328373 sequences. (Running on oeis4.)