a(1) = 1; for n>1 a(n) is smallest prime not occurring earlier such that the concatenation of a(n), a(n+1), ..., a(2n-1) is a composite number.
1, 2, 5, 3, 7, 11, 13, 17, 23, 19, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83
2 seqfan posts
Sun Jan 4 19:22:23 CET 2009 [seqfan] Re: Question related to sequence A083188