a(1)=a(2)=1; for n > 2, a(n) is the smallest integer such that a(n) > a(n-1) and a(n)+a(n-1) is prime.
1, 1, 2, 3, 4, 7, 10, 13, 16, 21, 22, 25, 28, 31, 36, 37, 42, 47, 50, 51, 52, 55, 58, 69, 70
2 seqfan posts
Mon Mar 23 15:10:04 CET 2009 [seqfan] Re: Sum of two consecutive digits is a prime