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A162410 Numbers n such that 10*n + 3 and 10*n + 7 are prime. 0
0, 1, 4, 10, 16, 19, 22, 31, 46, 61, 64, 67, 82, 85, 88, 109, 121, 130, 142, 148, 166, 169, 178, 187, 199, 208, 220, 229, 247, 268, 283, 295, 316, 325, 334, 346, 361, 367, 379, 394, 400, 415, 451, 478, 481, 493, 523, 541, 550, 565, 592, 604, 673, 682, 724, 757 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..56.

EXAMPLE

10*0 + 3 = 3 and 10*0 + 7 = 7 are prime, hence 0 is a term; 10*10 + 3 = 103 and 10*10 + 7 = 107 are prime, hence 10 is a term.

MATHEMATICA

f1[n_]:=10*n+3; f2[n_]:=10*n+7; lst={}; Do[p1=f1[n]; p2=f2[n]; If[PrimeQ[p1]&&PrimeQ[p2], AppendTo[lst, n]], {n, 0, 2*6!}]; lst

Select[Range[0, 1000], And@@PrimeQ[10#+{3, 7}]&] (* Harvey P. Dale, May 11 2014 *)

PROG

(MAGMA) [ n: n in [0..760] | IsPrime(10*n+3) and IsPrime(10*n+7) ]; // Klaus Brockhaus, Jul 07 2009

CROSSREFS

Cf. A076746.

Sequence in context: A310484 A310485 A255243 * A310486 A310487 A310488

Adjacent sequences:  A162407 A162408 A162409 * A162411 A162412 A162413

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 02 2009

EXTENSIONS

Edited and listed terms verified by Klaus Brockhaus, Jul 07 2009

STATUS

approved

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Last modified January 27 23:50 EST 2020. Contains 331301 sequences. (Running on oeis4.)