A192671 Floor-Sqrt transform of Riordan numbers (A005043).

1, 0, 1, 1, 1, 2, 3, 6, 9, 15, 24, 39, 64, 106, 174, 288, 476, 791, 1315, 2192, 3659, 6120, 10251, 17195, 28880, 48565, 81760, 137786, 232427, 392429, 663130, 1121446, 1897924, 3214257, 5447110, 9236757, 15672057, 26605536, 45190288, 76795140, 130565138, 222083192, 377911330, 643341150

Offset: 0

Author

Emanuele Munarini, Jul 07 2011

Keywords

• nonn

Programs

Mathematica

FSFromSeries[f_,x_,n_] := Map[Floor[Sqrt[#]]&,CoefficientList[Series[f,{x,0,n}],x]]
FSFromSeries[(1+x-Sqrt[1-2x-3x^2])/(2x(1+x)),x,100]

Formula

a(n) = floor(sqrt(RiordanN(n))).