0,5

Table of n, a(n) for n=0..20.

John Riordan, Letter to N. J. A. Sloane, Sep 26 1980 with notes on the 1973 Handbook of Integer Sequences. Note that the sequences are identified by their N-numbers, not their A-numbers.

Riordan gives a recurrence.

Sequence in context: A125793 A121145 A144882 * A006681 A074876 A238722

Adjacent sequences: A298009 A298010 A298011 * A298013 A298014 A298015

nonn

N. J. A. Sloane, Jan 10 2018

approved