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%I #8 Sep 01 2021 03:40:45
%S 1,3,9,3,11,1,23,49,21,3,17,9,13,3,47,19,41,43,3,51,371,183,3,21,103,
%T 53,33,33,91,41,99,433,443,93,111,501,73,11,139,177,171,429,521,333,
%U 417,1,341,213,253,171,387,171,779,463,687,861,1131,39,539,231,1513,263,369
%N a(1) = 1; then numbers such that the concatenation a(n)a(n-1)...a(2)a(1)a(2)...a(n-1)a(n) is a prime for n>1.
%Y Cf. A083997, A083998, A083999, A084000, A083401.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, May 23 2003
%E More terms from _Ray Chandler_, Jun 22 2003, Aug 03 2003