%I A006237 M3725
%S A006237 1,1,4,384,42467328,20776019874734407680,1657509127047778993870601546036901052416000000,
%T A006237 153850844349814660487100539994381178281567942393055761257560677644718869248475136000000000000000000000
%N A006237 Complexity of tensor sum of n graphs; or spanning trees on n-cube.
%D A006237 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A006237 G. Kreweras, Complexite et circuits Euleriens dans la sommes tensorielles 
               de graphes, J. Combin. Theory, B 24 (1978), 202-212.
%D A006237 R. P. Stanley, Enumerative Combinatorics, Cambridge, Vol. 2, 1999; see 
               Example 5.6.10.
%H A006237 <a href="Sindx_Tra.html#trees">Index entries for sequences related to 
               trees</a>
%F A006237 a(n) = 2^(2^n-1-n)*1^binomial(n, 1)*2^binomial(n, 2)*...*n^binomial(n, 
               n).
%o A006237 (PARI) a(n)=2^(2^n-n-1)*prod(k=1,n,k^binomial(n,k))
%Y A006237 Cf. A006235.
%Y A006237 Sequence in context: A154569 A038015 A003753 this_sequence A116031 A115049 
               A158111
%Y A006237 Adjacent sequences: A006234 A006235 A006236 this_sequence A006238 A006239 
               A006240
%K A006237 nonn,easy,nice
%O A006237 0,3
%A A006237 N. J. A. Sloane (njas(AT)research.att.com), D. E. Knuth
%E A006237 Description expanded 7/95.