Invitation: celebrating 50 years of OEIS, 250000 sequences, and Sloane's 75th, there will be a conference at DIMACS, Rutgers, Oct 9-10 2014.
Table of n, a(n) for n=1..21.
Cf. A067633. [From R. J. Mathar, Sep 08 2008]
Sequence in context: A095126 A077842 A067633 * A108489 A155375 A155307
Adjacent sequences: A091871 A091872 A091873 * A091875 A091876 A091877
Ray Chandler, Feb 07 2004