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A167518
Least reversible prime (A007500) which is a concatenation of n consecutive primes.
1
2, 151157, 353359367, 139149151157, 101103107109113, 704517045770459704817048770489, 97101103107109113127, 1519315199152171522715233152411525915263, 382138233833384738513853386338773881, 9319932393379341934393499371937793919397
OFFSET
1,1
COMMENTS
Here the weaker definition of A007500 is used, but all terms > 2 known so far are also Emirps in the sense of A006567 (i.e. different from their reversal), so it is sufficient to change the first term to 13 in order to have a sequence of "true" emirps.
Is it possible to prove that all terms > 2 are in A006567?
PROG
(PARI) for(k=1, 19, for(i=0, 1e9, isprime( eval( p=concat( vector( k, j, Str( prime( i+j )))))) & isprime(eval(concat(vecextract(Vec(p), "-1..1")))) & break); print1(p, ", "))
CROSSREFS
Sequence in context: A003840 A122540 A324438 * A178168 A271669 A006935
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Nov 10 2009
EXTENSIONS
Edited by Charles R Greathouse IV, Apr 28 2010
a(9)-a(10) from Donovan Johnson, Sep 25 2011
STATUS
approved