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A142160 Primes congruent to 2 mod 39. 5
2, 41, 197, 353, 431, 509, 587, 743, 821, 977, 1289, 1367, 1523, 1601, 1913, 2069, 2381, 2459, 2693, 2927, 3083, 3863, 4019, 4253, 4409, 4643, 4721, 4799, 4877, 5189, 5501, 5657, 5813, 6047, 6203, 6359, 6827, 6983, 7451, 7529, 7607, 7841, 7919, 8231, 8387 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(4)..a(7) are the first set of 4 prime-indexed primes in arithmetic progression: a(4) = 353 = prime(prime(20)); a(5) = 431 = prime(prime(23)); a(6) = 509 = prime(prime(25)); a(7) = 587 = prime(prime(28)). Then we can see that 431-353 = 509-431 = 587-509 = 78. - Bobby Jacobs, Nov 30 2016

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

FORMULA

a(n) ~ 24n log n. - Charles R Greathouse IV, Jul 03 2016

MATHEMATICA

Select[Prime[Range[3000]], MemberQ[{2}, Mod[#, 39]]&] (* Vincenzo Librandi, Aug 19 2012 *)

Select[Range[2, 9000, 39], PrimeQ] (* Harvey P. Dale, Oct 21 2014 *)

PROG

(MAGMA)[p: p in PrimesUpTo(9000) | p mod 39 eq 2 ]; // Vincenzo Librandi, Aug 19 2012

(PARI) is(n)=isprime(n) && n%39==2 \\ Charles R Greathouse IV, Jul 03 2016

CROSSREFS

Cf. A000040.

Sequence in context: A287335 A212837 A063271 * A174615 A109125 A037061

Adjacent sequences:  A142157 A142158 A142159 * A142161 A142162 A142163

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Jul 11 2008

STATUS

approved

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Last modified May 17 08:41 EDT 2021. Contains 343966 sequences. (Running on oeis4.)