%I #7 Dec 20 2019 11:04:33
%S 3,9,17,29,47,51,81,87,113,117,131,141,201,239,291,333,359,371,393,
%T 443,459,489,509,539,573,623,663,681,749,819,821,873,903,947,1071,
%U 1077,1161,1269,1533,1563,1589,1613,1637,1673,1767,1773,1821,1841,1883,1959,1977
%N Numbers n such that the strings n1n and 1n1 are both prime.
%H Daniel Starodubtsev, <a href="/A090262/b090262.txt">Table of n, a(n) for n = 1..10000</a>
%e 9 is a member as 919 and 191 are both prime.
%Y Cf. A090263, A090264, A090265.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Nov 28 2003
%E More terms from mohammed bouayoun (bouyao(AT)wanadoo.fr), Feb 02 2004