A192681 Floor-sqrt transform of Lah partition numbers (A000262).

1, 1, 1, 3, 8, 22, 63, 193, 627, 2143, 7677, 28706, 111669, 450529, 1880164, 8097765, 35922614, 163849371, 767224522, 3682984346, 18102428784, 91000840873, 467393250911, 2450438244585, 13102651355735, 71398380128514, 396202573696587

Offset

0,4

Links

Table of n, a(n) for n=0..26.

Formula

a(n) = floor(sqrt(A000262(n))).

Maple

A000262 := proc(n) option remember: if n=0 then RETURN(1) fi: if n=1 then RETURN(1) fi: (2*n-1)*procname(n-1) - (n-1)*(n-2)*procname(n-2) end proc:
A192681 := proc(n) floor(sqrt(A000262(n))) ; end proc: # R. J. Mathar, Jul 13 2011

Mathematica

FSFromExpSeries[f_, x_, n_] := Map[Floor[Sqrt[#]]&, CoefficientList[Series[f, {x, 0, n}], x]Table[k!, {k, 0, n}]]
FSFromExpSeries[Exp[x/(1-x)], x, 60]

Crossrefs

Sequence in context: A317997 A164934 A047926 * A339288 A014138 A099324

Adjacent sequences: A192678 A192679 A192680 * A192682 A192683 A192684

Keyword

nonn

Author

Emanuele Munarini, Jul 07 2011

Extensions

All terms replaced by R. J. Mathar, Jul 13 2011

Status

approved