查看“︁韦德伯恩-埃瑟林顿数”︁的源代码

在[[图论]]中，'''韦德伯恩-埃瑟林顿数'''是由计算每张图有多少弱[[二叉树]]问题而得出的數列。

最初的几个韦德伯恩-埃瑟林顿数为：
1, 1, [[1]], [[2]], [[3]], [[6]], [[11]], [[23]], [[46]], [[98]], 207, 451, 983, 2179, 4850, 10905, 24631, 56011, 127912, 293547, 676157, 1563372, 3626149, 8436379, 19680277, 46026618, 107890609, 253450711, 596572387, 1406818759, 3323236238, 7862958391,... {{OEIS | id = A001190}}

==组合意义上的诠释==
[[File:Wedderburn-Etherington trees.svg|thumb|360px|奥特树与弱二叉树，两种通过韦德伯恩-埃瑟林顿数计数的有根二叉树。]]

==名字由來==
韦德伯恩-埃瑟林顿数的名字由來是兩個數學家[[艾弗·埃瑟林顿]]和[[约瑟夫·韦德伯恩]]。

==參考資料==
*OEIS.A001190 
* S. J. Cyvin et al., "Enumeration of constitutional isomers of polyenes," ''J. Molec. Structure (Theochem)'' '''357''' (1995): 255–261
* I. M. H. Etherington, "Non-associate powers and a functional equation," ''Math. Gaz.'' '''21''' (1937): 36–39, 153
* I. M. H. Etherington, "On non-associative combinations," ''Proc. Royal Soc. Edinburgh'', '''59''' 2 (1939): 153–162. 
* S. R. Finch, ''Mathematical Constants''. Cambridge: Cambridge University Press (2003): 295–316
* F. Murtagh, "Counting dendrograms: a survey," ''Discrete Applied Mathematics'' '''7''' (1984): 191–199
* J. H. M. Wedderburn, "The functional equation <math>g(x^2) = 2ax + [ g(x) ]^2</math>" ''Ann. Math.'' '''24''' (1923): 121–140

[[Category:整數數列]]