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A167518
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Least reversible prime (A007500) which is a concatenation of n consecutive primes.
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1
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2, 151157, 353359367, 139149151157, 101103107109113, 704517045770459704817048770489, 97101103107109113127, 1519315199152171522715233152411525915263, 382138233833384738513853386338773881, 9319932393379341934393499371937793919397
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OFFSET
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1,1
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COMMENTS
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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?
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LINKS
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PROG
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(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, ", "))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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