A155508 Lesser of emirps (pairs) with digits 1 and 9 only.
199, 91199, 111119, 111919, 119191, 991999, 1191119, 1191191, 1191991, 11111911, 11191991, 11919991, 19111991, 91111199, 111111199, 111199199, 191111119, 199991999, 919919999, 1111111999, 1191111991, 1199111191, 1911199999
Offset: 1
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..660
Programs
-
Mathematica
Flatten[Table[Select[Subsets[Select[FromDigits/@Tuples[{1,9},n],PrimeQ],{2}],AllTrue[#,PrimeQ]&&#[[1]]==IntegerReverse[#[[2]]]&][[All,1]],{n,3,10}]/.{}->Nothing] (* Harvey P. Dale, Aug 21 2020 *)
Extensions
More terms from Sean A. Irvine, Apr 06 2010