%I A001173 M4010 N1662
%S A001173 1,5,52,1522,145984,48464496,56141454464,229148550030864,
%T A001173 3333310786076963968,174695272746749919580928,
%U A001173 33301710992539090379269318144,23278728241293494533015563325552128
%N A001173 Relations on n unlabeled points.
%D A001173 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A001173 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A001173 R. L Davis, The number of structures of finite relations, Proc. Amer. 
               Math. Soc. 4 (1953), 486-495.
%D A001173 M. D. McIlroy, Calculation of numbers of structures of relations on finite 
               sets, Massachusetts Institute of Technology, Research Laboratory 
               of Electronics, Quarterly Progress Reports, No. 17, Sept. 15, 1955, 
               pp. 14-22.
%D A001173 W. Oberschelp, Kombinatorische Anzahlbestimmungen in Relationen, Math. 
               Ann., 174 (1967), 53-78.
%Y A001173 Cf. A000595, A001174.
%Y A001173 Sequence in context: A108459 A076281 A099977 this_sequence A107803 A088712 
               A090153
%Y A001173 Adjacent sequences: A001170 A001171 A001172 this_sequence A001174 A001175 
               A001176
%K A001173 nonn,nice
%O A001173 1,2
%A A001173 N. J. A. Sloane (njas(AT)research.att.com).
%E A001173 More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Apr 18 2000