%I #10 Jan 17 2022 14:46:34
%S 3,1,1,2,1,6,11,16,11,1,8,21,13,11,34,41,12,4,66,24,15,17,4,122,70,96,
%T 33,2,43,5,3,100,44,28,23,27,12,4,113,10,3,90,9,162,15,9,69,146,9,145,
%U 74,3,42,99,31,93,35,259,53,79,14,285,84,1,36,78,147,78,66,246,155,624
%N Beginning with 3 the smallest number such that the concatenation a(n), a(n-1), ... a(2), a(1) is a prime.
%H Harvey P. Dale, <a href="/A089338/b089338.txt">Table of n, a(n) for n = 0..200</a>
%e 3, 13, 113, 2113, 12113, 612113, ...etc. are primes.
%t nxt[{cnc_,a_}]:=Module[{k=1},While[!PrimeQ[k*10^IntegerLength[ cnc]+ cnc],k++];{k*10^IntegerLength[cnc]+cnc,k}]; NestList[nxt,{3,3},80][[All,2]] (* _Harvey P. Dale_, Jan 17 2022 *)
%K base,nonn
%O 0,1
%A _Amarnath Murthy_, Nov 04 2003
%E More terms from _Ray Chandler_, Nov 07 2003
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