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A192665
Floor-Sqrt transform of the numbers binomial(3*n,n)/(2*n+1) (A001764).
1
1, 1, 1, 3, 7, 16, 37, 88, 207, 496, 1196, 2900, 7075, 17344, 42693, 105473, 261397, 649638, 1618527, 4041401, 10111385, 25343883, 63627940, 159982510, 402802976, 1015454569, 2562911901, 6475519561, 16377581829, 41459980288, 105047450207, 266375717828, 675980743615
OFFSET
0,4
FORMULA
a(n) = floor(sqrt(binomial(3*n,n)/(2*n+1))).
MATHEMATICA
Table[Floor[Sqrt[Binomial[3n, n]/(2n+1)]], {n, 0, 100}]
PROG
(Maxima) makelist(floor(sqrt(binomial(3*n, n)/(2*n+1))), n, 0, 12);
CROSSREFS
Cf. A001764.
Sequence in context: A123392 A095263 A010912 * A052967 A297498 A239040
KEYWORD
nonn
AUTHOR
Emanuele Munarini, Jul 07 2011
STATUS
approved