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A089923 Largest prime in the reverse concatenation of the first n consecutive prime numbers when that concatenation is a pseudoprime. +0
1
5, 17, 89, 383 (list; graph; listen)
OFFSET

5,1

EXAMPLE

53 is the reverse concatenation of the consecutive primes 3 and 5. 53 is prime.

PROGRAM

(PARI) revprime2(n) = { y=3; forprime(x=5, n, y=concat(Str(x), Str(y)); z=eval(y); if(ispseudoprime(z), print(x", "z)) ) }

CROSSREFS

Sequence in context: A036756 A012782 A026685 this_sequence A139390 A076516 A034821

Adjacent sequences: A089920 A089921 A089922 this_sequence A089924 A089925 A089926

KEYWORD

nonn,base

AUTHOR

Cino Hilliard (hillcino368(AT)gmail.com), Jan 11 2004

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Last modified September 6 16:04 EDT 2008. Contains 143483 sequences.


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