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%I #10 Jul 03 2024 18:44:33
%S 3,7,17,23,29,31,41,43,53,67,71,83,109,127,139,151,173,179,197,211,
%T 229,263,271,281,307,359,463,547,557,569,587,593,673,677,683,691,701,
%U 719,727,757,769,823,839,881,883,887,907,937,983,997,1087,1103,1171,1181
%N Concatenation of prime k and its 10's complement is a prime.
%H Robert Israel, <a href="/A083989/b083989.txt">Table of n, a(n) for n = 1..10000</a>
%e 43 belongs to this sequence as 4357 is also a prime.
%p g:= proc(n) local c; c:= 10^(1+ilog10(n))-n; n*10^(1+ilog10(c))+c end proc:
%p select(t -> isprime(t) and isprime(g(t)), [seq(i,i=3..10000,2)]); # _Robert Israel_, Jul 03 2024
%Y Cf. A083990, A089186.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, May 23 2003
%E More terms from _Jason Earls_, Jun 01 2003