A090508 Least number beginning with prime(n) such that every concatenation is a prime.

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

Offset

1,1

Links

Table of n, a(n) for n=1..38.

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 A355648 A347894

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