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A107646 Primes from concatenating twin primes. 0
3557, 355711131719 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..2.

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

Sequence in context: A151810 A083955 A104207 * A204607 A204600 A204599

Adjacent sequences:  A107643 A107644 A107645 * A107647 A107648 A107649

KEYWORD

hard,more,nonn,bref,base

AUTHOR

Parthasarathy Nambi, Jun 09 2005

STATUS

approved

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Last modified July 12 13:27 EDT 2020. Contains 335663 sequences. (Running on oeis4.)