1,4

Inspired by A122480.

Table of n, a(n) for n=1..102.

Cf. A060864 (indices of 0 terms), A000040 (indices of 1 terms), A024675 (indices of 2 terms).

Sequence in context: A130911 A118829 A118832 * A105700 A236831 A030205

Adjacent sequences: A122804 A122805 A122806 * A122808 A122809 A122810

nonn

Ray Chandler, Sep 25 2006

approved