1,5

Just as for A005185, it is not known if this sequence exists for all n.

Table of n, a(n) for n=1..74.

Cf. A005185.

Sequence in context: A029149 A080570 A163001 * A323701 A226591 A194223

Adjacent sequences: A239910 A239911 A239912 * A239914 A239915 A239916

nonn

N. J. A. Sloane, Apr 09 2014

approved