[seqfan] Smallest emirp with a given digit sum

[Jack Brennen]

Possibly another emirp sequence -- doesn't seem to be present in OEIS...

a(n) = Smallest emirp with digit sum n, or 0 if no such emirp exists.


0, 0, 0, 0, 13, 113, 0, 1033, 17, 0, 37, 1091, 0, 157, 149, 0,
79, 179, 0, 199, 389, 0, 769, 1499, 0, 1789, 1979, 0, 3889, 7589, 0,
7699, 16979, 0, 37897, 18899, 0, 39799, 39989, 0, 77899, 79889, 0,
179989, 98999, 0, 749899, 389999, 0, 789979, 979889, 0,
1798999, 1799999, 0, 7789879, 7688999, 0, 7888999, 9889799, 0,
17989999, 36998999, 0, 77798989, 77799989, 0, 79879999, 98979989, 0,
189997999, 189989999, 0, 769798999, 398999999, 0, 789889999, 797999999, 0,
...

Open questions:

After a(34) = 37897, do all of the following sequence members end with a 9?

Is a(11) = 1091 the only sequence member to end with a 1?