343440

Appears in sequences

• Scaled Chebyshev U-polynomial evaluated at sqrt(6)/2.at n=8A030192
• Triangle, T(n, k) = (sqrt(k+1))^(n-1)*ChebyshevU(n-1, sqrt(k+1)/2), read by rows.at n=50A167925
• Number of permutations of {1,...,n} avoiding adjacent step pattern up, up, down, up, down, down.at n=9A177550
• Number of active (ON, black) cells at stage 2^n-1 of the two-dimensional cellular automaton defined by "Rule 478", based on the 5-celled von Neumann neighborhood.at n=9A272452