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%I #24 Jan 20 2024 11:29:06
%S 1,1,1,1,2,2,2,2,2,6,6,6,6,6,6,6,24,24,24,24,24,24,24,24,24,120,120,
%T 120,120,120,120,120,120,120,120,120,720,720,720,720,720,720,720,720,
%U 720,720,720,720,720,5040,5040,5040,5040,5040,5040,5040,5040,5040
%N a(n) = (floor(sqrt(n)))!
%H Vincenzo Librandi, <a href="/A214080/b214080.txt">Table of n, a(n) for n = 0..1000</a>
%F Sum_{n>=0} 1/a(n) = 3*e. - _Amiram Eldar_, Aug 15 2022
%F a(n) = A000142(A000196(n)). - _Michel Marcus_, Aug 15 2022
%t Table[Floor[Sqrt[n]]!, {n, 0, 100}] (* _T. D. Noe_, Dec 23 2012 *)
%o (Derive) PROG(y := [], n := 50, LOOP(IF( = -1, RETURN y), y := ADJOIN(FLOOR(SQRT(n))!, y), n := n - 1))
%o (Magma) [Factorial(Floor(Sqrt(n))): n in [0..60]]; // _Vincenzo Librandi_, Feb 13 2013
%o (PARI) a(n) = floor(sqrt(n))!; \\ _Altug Alkan_, Jan 11 2016
%Y Cf. A214078, A214079, A214080, A214081, A214083, A055228, A055226.
%Y Cf. A000142, A000196.
%K easy,nonn
%O 0,5
%A _Mohammad K. Azarian_, Dec 22 2012