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%I #18 Mar 25 2019 13:54:47
%S 3,313,13331,33533,1333331,3331333,323333323,13333633331,31333333313,
%T 1333335333331,3233333333323,133333353333331,332333333333233,
%U 333333313333333,33233333333333233,1333333336333333331,3333333313133333333,133333333383333333331
%N Smallest palindromic prime containing exactly n 3's.
%H Chai Wah Wu, <a href="/A083974/b083974.txt">Table of n, a(n) for n = 1..500</a>
%t Table[d = 3; i = 1;
%t While[ x = IntegerDigits[Prime[i]];
%t x != Reverse[x] || Count[x, d] != n , i++];
%t FromDigits[x], {n, 1, 6}] (* _Robert Price_, Mar 25 2019 *)
%Y Cf. A083972, A083973, A083975, A083976, A083977, A083978, A083979, A083980, A083981.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 21 2003
%E More terms from _Giovanni Resta_, Feb 08 2006