477638700

Appears in sequences

• Symmetrical dissections of an n-gon.at n=34A000063
• Symmetrical dissections of an n-gon.at n=33A000063
• Expansion of (sqrt(1-4x^2) - sqrt(1-4x))/(2x).at n=18A000912
• a(n) = T(n, floor(n/2)), where T = Catalan triangle (A008315).at n=34A026008
• a(n) = floor( binomial(n, floor(n/2))/(1 + ceiling(n/2)) ) (interpolates between Catalan numbers).at n=36A028303
• a(n) = ceiling( binomial(n, floor(n/2))/(1 + ceiling(n/2)) ) (interpolates between Catalan numbers).at n=36A028304
• Number of prime binary rooted trees with n external nodes.at n=17A035010
• Catalan numbers with even index (A000108(2*n), n >= 0): a(n) = binomial(4*n, 2*n)/(2*n+1).at n=9A048990
• G.f.: A(x) = (x-2*x^2-2*x^3-(1+x)*sqrt(1-4*x^2)+sqrt(1-4*x^6))/(2*x^2).at n=35A063786
• G.f.: A(x) = (x-2*x^2-2*x^3-(1+x)*sqrt(1-4*x^2)+sqrt(1-4*x^6))/(2*x^2).at n=34A063786
• Quotient C[p(n),{p(n)+-1}/2]/p(n), where p(n)=n-th prime.at n=10A075891
• Number of fixed points in range [A014137(n-1)..A014138(n-1)] of permutation A089864.at n=37A089408
• Number of fixed points in range [A014137(n-1)..A014138(n-1)] of permutation A089851/A089853.at n=19A089848
• Carlitz-Riordan q-Catalan numbers (recurrence version) for q = -1.at n=37A090192
• Largest gcd of two distinct numbers on row n of Pascal's triangle.at n=34A092394
• Expansion of 1 + 2x/(1 + sqrt(1 - 4x^2)).at n=37A097331
• An inverse Chebyshev transform of 1-x.at n=36A099363
• An inverse Chebyshev transform of (1-x)^2.at n=34A099364
• Expansion of c(-x^2)(1+2x-sqrt(1+4x^2))/2, c(x) the g.f. of A000108.at n=36A106181
• Expansion of c(-x^2)(1+2x-sqrt(1+4x^2))/2, c(x) the g.f. of A000108.at n=37A106181