



17, 1447, 2053, 34367, 50383, 94427, 140473, 154487, 190523, 220553, 286619, 4303763, 4763809, 6443977, 8504183, 9044237, 11304463, 13404673, 15504883, 17005033, 18145147, 18345167, 19605293, 21205453, 22345567, 22605593
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..26.


MATHEMATICA

a = {51}; For[n = 3, n < 500, n++, If[Prime[n + 1] == Prime[n] + 2, AppendTo[a, FromDigits[Join[IntegerDigits[Prime[n + 1]], IntegerDigits[Prime[n]]]]]]]; Select[a/3, PrimeQ[ # ] &]


PROG

(PARI) concattwins3r(n) = { local(x, y); forprime(x=2, n, if(isprime(x+2), y=floor(eval(concat(Str(x+2), Str(x)))/3); print1(y", ") ) ) }


CROSSREFS

Sequence in context: A072160 A078814 A242282 * A104808 A061686 A133590
Adjacent sequences: A129908 A129909 A129910 * A129912 A129913 A129914


KEYWORD

nonn,less


AUTHOR

Cino Hilliard, Jun 05 2007


EXTENSIONS

Edited and extended by Stefan Steinerberger, Aug 02 2007


STATUS

approved



