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 A090508 Least number beginning with prime(n) such that every concatenation is a prime. 1
 2, 3, 51, 71, 1137, 1321, 1727, 1947, 2383, 2919, 311, 3723, 4173, 43197, 47307, 531, 59103, 6117, 67279, 7191, 73457, 79159, 8379, 8913, 97697, 1011483, 10399, 107151, 10959, 113529, 12713, 1311171, 137649, 139101, 149107, 1511229, 15743, 163639 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS MAPLE l:=[]: for n from 1 to 40 do p:=ithprime(n): m:=p: lcon:=cat(op(l)): for i from 1 do if(isprime(parse(cat(lcon, m)))) then l:=[op(l), m]: break fi: m:=parse(cat(p, 2*i-1)) od od: op(l); (C. Ronaldo) CROSSREFS Cf. A090509. Sequence in context: A113700 A065646 A268251 * A126716 A193332 A192182 Adjacent sequences:  A090505 A090506 A090507 * A090509 A090510 A090511 KEYWORD base,nonn AUTHOR Amarnath Murthy, Dec 06 2003 EXTENSIONS More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 18 2005 STATUS approved

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