%I #11 Aug 07 2020 02:15:14
%S 2,3,509,79,1163,13033,1721,19,233,29569,3119,37057,410171,43003,
%T 47111,5323,59219,61291,670223,710911,73331,795793,83399,894709,
%U 975581,101383,1033079,1071937,109073,1130257,1276397,1313911,1378673,1395469,1491233
%N a(n) is the least prime beginning with prime(n) such that the concatenation a(1)a(2)...a(n) is a prime.
%H Robert Israel, <a href="/A090510/b090510.txt">Table of n, a(n) for n = 1..461</a>
%p dcat:= proc(a,b) 10^(1+ilog10(b))*a+b end proc:
%p S:= 2: R:= 2:
%p for n from 2 to 35 do
%p found:= false;
%p for d from 0 while not found do
%p cand:= 10^d*ithprime(n)-1;
%p do
%p cand:= nextprime(cand);
%p if cand >= 10^d*(ithprime(n)+1) then break fi;
%p Sc:= dcat(S,cand);
%p if isprime(Sc) then found:= true; break fi
%p od od;
%p R:= R, cand;
%p S:= Sc;
%p od:
%p R; # _Robert Israel_, Aug 06 2020
%Y Cf. A090511.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Dec 06 2003
%E More terms from _Max Alekseyev_, Feb 08 2010