%N First differences of A067186 (A067186 gives n such that 1+t(n) is prime, where t(n) is the n-th triangular number).
%C Conjecture. Except for the first term a(1)=2, this sequence does not contain terms of the form 4k+2. (This has been confirmed for the first several thousand terms.)
%Y Cf. A000217, A067186.
%A _John W. Layman_, Oct 26 2007