a(n) is the least prime factor of the concatenation of 2^n and 3^n.

Terms

a(0) =11a(1) =23a(2) =7a(3) =827a(4) =41a(5) =19a(6) =7a(7) =1282187a(8) =2566561a(9) =1163a(10) =7a(11) =79a(12) =41a(13) =167a(14) =7a(15) =11a(16) =17a(17) =17a(18) =7a(19) =29a(20) =41a(22) =7a(24) =2566561a(25) =11a(26) =7a(27) =35393a(28) =29a(29) =179a(30) =7a(31) =19