A192663 Floor-Sqrt transform of the binomial coefficients binomial(3*n,n) (A005809).

1, 1, 3, 9, 22, 54, 136, 340, 857, 2164, 5481, 13911, 35379, 90124, 229913, 587254, 1501615, 3843314, 9845118, 25238541, 64744455, 166190960, 426829202, 1096784835, 2819620836, 7251796132, 18658280277, 48023738374, 123648031266, 318460151301, 820446813941

Offset

0,3

Links

Table of n, a(n) for n=0..30.

Formula

a(n) = floor(sqrt(binomial(3*n,n))).

a(n) ~ 3^(3*n/2 + 1/4) / (2^(n+1/2) * (Pi*n)^(1/4)). - Amiram Eldar, Dec 15 2025

Mathematica

Table[Floor[Sqrt[Binomial[3n, n]]], {n, 0, 100}]

Prog

(Maxima) makelist(floor(sqrt(binomial(3*n, n))), n, 0, 24);

Crossrefs

Cf. A005809.

Sequence in context: A336511 A054442 A354648 * A114697 A032284 A329163

Adjacent sequences: A192660 A192661 A192662 * A192664 A192665 A192666

Keyword

nonn,easy

Author

Emanuele Munarini, Jul 07 2011

Status

approved