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A107646 Primes from concatenating twin primes. +0
1
3557, 355711131719 (list; graph; listen)
OFFSET

1,1

LINKS

Chris Caldwell The First 1,008 Twin Primes.

EXAMPLE

3557 is a prime produced by concatenating twin primes (3,5) and (5,7).

355711131719 is a prime produced by concatenating twin primes (3,5), (5,7), (11,13) and (17,19).

MATHEMATICA

tw = Select[ Prime@ Range@100000, PrimeQ[ # + 2] &]; tw = Flatten /@ IntegerDigits@ Transpose[{tw, tw + 2}]; t = {}; Do[p = FromDigits@ Flatten@ Table[ tw[[i]], {i, n}]; If[ PrimeQ[p], Print[p]], {n, 1090}] (* Robert G. Wilson v *)

CROSSREFS

Adjacent sequences: A107643 A107644 A107645 this_sequence A107647 A107648 A107649

Sequence in context: A151810 A083955 A104207 this_sequence A071144 A152217 A004932

KEYWORD

hard,more,nonn,bref

AUTHOR

Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Jun 09 2005

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Last modified November 8 20:39 EST 2009. Contains 166234 sequences.


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