1,1

CRC Handbook of Combinatorial Designs, 1996, p. 418.

Sequence in context: A145195 A096022 A097222 this_sequence A110978 A087719 A116070

Adjacent sequences: A004066 A004067 A004068 this_sequence A004070 A004071 A004072

nonn,hard

N. J. A. Sloane (njas(AT)research.att.com).