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 A283103 Number of A'Campo forests of degree n and co-dimension 5. 2
 0, 0, 0, 4, 1380, 75600, 2340744, 54275296, 1055436228, 18230184752, 289150871152, 4300858168200, 60843411796440 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS a(n) is the number of A'Campo forests of degree n and of co-dimension 5. REFERENCES P. Flajolet and R. Sedgewick, Analytic Combinatorics, Cambridge University Press (2009). LINKS Table of n, a(n) for n=1..13. N. Combe, V. Jugé, Counting bi-colored A'Campo forests, arXiv:1702.07672 [math.AG], 2017. FORMULA a(n) is obtained by using the generating function N_{1} =1+yN_{2}^4 and (1-N_{2} +2yN_{2}^4 -yN_{2}^{5} +xyN_{2}^{6} +y^{2}N_{2}^{8})(1+yN_{2}^{4}-xyN_{2}^{5})+x^3y^{2}N_{2}^{9} =0, where N_{1}(x,y)=\sum_{n}N_{1}'(5,n)x^{5}y^{n} and N_{1}'(5,n) is the number of A'Campo forests with co-dimension 5; N_{2}(x,y)=\sum_{n}N_{2}'(5,n)x^{5}y^{n} where N_{2}'(5,n) is the number of partial configurations. EXAMPLE For n<4, the number of A'Campo forests of degree n and co-dimension 5 is zero. For n = 4 the number of A'Campo forests of co-dimension 5 is 4. CROSSREFS Cf. A283101, A283102, A283049, A277877. Sequence in context: A172925 A167071 A274296 * A278844 A036107 A201390 Adjacent sequences: A283100 A283101 A283102 * A283104 A283105 A283106 KEYWORD nonn AUTHOR Noemie Combe, Feb 28 2017 EXTENSIONS Added crossrefs STATUS approved

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Last modified October 2 14:37 EDT 2023. Contains 365837 sequences. (Running on oeis4.)