A192677 Floor-Sqrt transform of involution numbers (A000085).

1, 1, 1, 2, 3, 5, 8, 15, 27, 51, 97, 188, 374, 753, 1546, 3217, 6797, 14553, 31580, 69352, 154138, 346341, 786692, 1804949, 4182366, 9781638, 23086472, 54960683, 131951799, 319359086, 779048952, 1914843089, 4741419557, 11824255970, 29693231388, 75068841641, 191035103175

Offset: 0

Author

Emanuele Munarini, Jul 07 2011

Keywords

• nonn

Programs

Mathematica

FSFromExpSeries[f_,x_,n_] := Map[Floor[Sqrt[#]]&,CoefficientList[Series[f,{x,0,n}],x]Table[k!,{k,0,n}]]
FSFromExpSeries[Exp[x+x^2/2],x,100]

Formula

a(n) = floor(sqrt(A000085(n))).