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%I #31 Feb 22 2016 03:06:50
%S 0,1,4,19,54,180,508,1533,4332,13041,37492,111367,326636,968802,
%T 2858460,8483290,25113618,74512947,220885446,655274837,1943117294,
%U 5763235194,17089323366,50673594159,150232437482,445359235627,1320070201468
%N Sum of the Wiener indices of all trees having n vertices.
%C C program, see the first Bomfim link, around the function Gen() of Gang Li & Frank Ruskey. - _Washington Bomfim_, Feb 23 2011
%H W. Bomfim, <a href="https://oeis.org/w/images/8/80/FreeWiener.txt">C program</a>
%H Stephan Wagner, <a href="http://www.math.tugraz.at/~wagner/Diss.pdf">Graph-theoretical enumeration and digital expansions: an analytic approach</a>, Dissertation, Fakult. f. Tech. Math. u. Tech. Physik, Tech. Univ. Graz, Austria, Feb. 2006, page 31
%H Stephan Wagner, <a href="http://finanz.math.tu-graz.ac.at/~wagner/avwiener.pdf">On the average Wiener index of degree-restricted trees</a>, Australas. J. Combinat. 37 (2007) 187, Table 2
%e a(4)=19; indeed, there are 2 trees on 4 vertices: the path abcd with Wiener index 1+1+1+2+2+3=10 and the star tree on 4 vertices with Wiener index 1+1+1+2+2+2 = 9. - _Emeric Deutsch_, Feb 20 2016
%Y Cf. A000055.
%K nonn
%O 1,3
%A _N. J. A. Sloane_, Sep 23 2006
%E a(11)-a(27) from _Washington Bomfim_, Feb 23 2011
%E Name edited by _Emeric Deutsch_, Feb 20 2016
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