0,1

Table of n, a(n) for n=0..3.

For n=0, the two sets are the empty set and a set containing a single isolated vertex. - Sean A. Irvine, Nov 20 2019

Cf. A027624, A027667, A027668.

Sequence in context: A176947 A280798 A118912 * A241569 A262299 A135970

Adjacent sequences: A027677 A027678 A027679 * A027681 A027682 A027683

nonn,hard,more

R. H. Hardin

a(0) corrected by Sean A. Irvine, Nov 20 2019

approved