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%I #9 Sep 03 2017 03:21:01
%S 1,7,11,13,17,31,37,47,49,53,59,67,73,79,83,89,97,109,119,121,137,163,
%T 167,169,181,187,191,203,209,217,221,229,251,253,257,259,271,299,301,
%U 307,313,319,323,329,331,343,347,359,361,371,373,389,391
%N Digit '3' concatenated with a(n) is a prime.
%H Seiichi Manyama, <a href="/A032666/b032666.txt">Table of n, a(n) for n = 1..10000</a>
%K nonn,base
%O 1,2
%A _Patrick De Geest_, May 15 1998
%E Edited by _Charles R Greathouse IV_, Aug 02 2010