

A130122


Primes prime(n) such that 10*prime(n)+prime(n+2) is prime.


1



3, 5, 7, 11, 13, 17, 41, 67, 89, 101, 109, 181, 193, 199, 223, 227, 283, 313, 337, 347, 367, 419, 421, 449, 461, 479, 491, 587, 641, 647, 709, 727, 773, 811, 823, 827, 857, 859, 863, 881, 887, 911, 953, 1021, 1049, 1063, 1091, 1181, 1217, 1361, 1399, 1447
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OFFSET

1,1


LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000


EXAMPLE

a(7)=41 because 10*41+47=457 and 457 is prime,
a(8)=67 because 10*67+73=743 and 743 is prime,
a(9)=89 because 10*89+101=991 and 991 is prime, ...


MAPLE

ts_p6_01:=proc(n) local a, b, i, ans; ans := [ ]: for i from 1 to n do a := 10*ithprime(i)+ithprime(i+2): if (isprime(a)=true) then ans := [ op(ans), ithprime(i) ]: fi od; RETURN(ans) end: ts_p6_01(1000);


MATHEMATICA

Select[Partition[Prime[Range[300]], 3, 1], PrimeQ[10#[[1]]+#[[3]]]&][[All, 1]] (* Harvey P. Dale, Apr 17 2017 *)


CROSSREFS

Cf. A129900.
Sequence in context: A136187 A333207 A328489 * A288893 A046494 A287441
Adjacent sequences: A130119 A130120 A130121 * A130123 A130124 A130125


KEYWORD

nonn


AUTHOR

Jani Melik, Aug 01 2007


STATUS

approved



