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 A112328 a(n)=(n+1)binomial(2n+2,n+1)-3*4^n+binomial(2n,n). 1
 2, 18, 108, 562, 2724, 12660, 57240, 253842, 1109748, 4798780, 20572392, 87580308, 370706408, 1561573032, 6551178288, 27387484242, 114146434068, 474476717292, 1967642119368, 8142727008732, 33634295542968, 138696447565272 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row sums of A112327. REFERENCES F. Ruskey, Average shape of binary trees, SIAM J. Alg. Disc. Meth., 1, 1980, 43-50 (Eq. (8)). LINKS FORMULA G.f.=4z[2-sqrt(1-4z)]/[(1-4z)^(3/2)(1+sqrt(1-4z)] MAPLE a:=n->(n+1)*binomial(2*n+2, n+1)-3*4^n+binomial(2*n, n): seq(a(n), n=1..25); CROSSREFS Cf. A112327. Sequence in context: A094251 A101570 A006043 * A038721 A064837 A224902 Adjacent sequences:  A112325 A112326 A112327 * A112329 A112330 A112331 KEYWORD nonn AUTHOR Emeric Deutsch, Sep 04 2005 STATUS approved

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Last modified June 16 13:25 EDT 2019. Contains 324152 sequences. (Running on oeis4.)