2,4
Table of n, a(n) for n=2..12.
R. Munafo, Classifications of N Elements
Sequence in context: A191587 A290411 A142868 * A100233 A015525 A062224
Adjacent sequences: A171872 A171873 A171874 * A171876 A171877 A171878
nonn
Robert Munafo, Jan 21 2010
approved