3,1

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

G. Kreweras, Les preordres totaux compatibles avec un ordre partiel. Math. Sci. Humaines No. 53 (1976), 5-30.

Sequence in context: A121546 A135703 A101147 this_sequence A000347 A089095 A158499

Adjacent sequences: A006325 A006326 A006327 this_sequence A006329 A006330 A006331

nonn

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