A055226 a(n) = floor(sqrt(n!)).

1, 1, 1, 2, 4, 10, 26, 70, 200, 602, 1904, 6317, 21886, 78911, 295259, 1143535, 4574143, 18859677, 80014834, 348776576, 1559776268, 7147792818, 33526120082, 160785623545, 787685471322, 3938427356614, 20082117944245, 104349745809073, 552166953567228, 2973510046012910, 16286585271694955, 90679869067935485

Offset: 0

Author

Henry Bottomley, Jun 21 2000

Keywords

• easy
• nonn

Links

• T. D. Noe, Table of n, a(n) for n=0..300

Crossrefs

Cf. A000142, A000196.

Programs

Mathematica

Table[Floor[Sqrt[n!]], {n, 0, 100}] (* Emanuele Munarini, Jul 07 2011 *)

Maxima

makelist(floor(sqrt(n!)),n,0,24); /* Emanuele Munarini, Jul 07 2011 */

PARI

a(n)=sqrtint(n!);

Formula

a(n) = A000196(A000142(n)).