1,1
Cf. A000043.
Sequence in context: A018138 A175125 A171925 * A070819 A195667 A005244
Adjacent sequences: A057222 A057223 A057224 * A057226 A057227 A057228
nonn
G. L. Honaker, Jr. (honak3r(AT)gmail.com), Sep 18 2000