7,1
CRC Handbook of Combinatorial Designs, 1996, p. 285.
Sequence in context: A011511 A020856 A202626 * A175296 A076266 A200102
Adjacent sequences: A011992 A011993 A011994 * A011996 A011997 A011998
nonn,hard
N. J. A. Sloane (njas(AT)research.att.com).