1,1

W. Oberschelp, ``Strukturzahlen in endlichen Relationssystemen,'' in Contributions to Mathematical Logic (Proceedings 1966 Hanover Colloquium), pp. 199-213, North-Holland Publ., Amsterdam, 1968.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

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

Sequence in context: A092414 A139298 A004819 this_sequence A017415 A046246 A151580

Adjacent sequences: A001372 A001373 A001374 this_sequence A001376 A001377 A001378

nonn

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