1,1

For n=1,2 there are numerous ways, while for each of n=3 and n=4 there is only one way: n=3:{1,4,6,7,10,11,13,16},{2,3,5,8,9,12,14,15} (see A133483-A133484), n=4: {1,2,3,4,8,9,10,11,12,16},{5,6,7,13,14,15}.

Presumably for n >= 4 there are no solutions.

Table of n, a(n) for n=1..4.

Cf. A133483, A133484, A135419.

Sequence in context: A233898 A088894 A015277 * A309963 A289290 A034818

Adjacent sequences: A135415 A135416 A135417 * A135419 A135420 A135421

nonn

Zak Seidov, Dec 01 2007

approved