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a(1)=1; a(n) = n!*Fibonacci(n+2), n > 1.
(Formerly M4207)
4

%I M4207 #25 May 26 2024 12:27:39

%S 1,6,30,192,1560,15120,171360,2217600,32296320,522547200,9300614400,

%T 180583603200,3798482688000,86044973414400,2088355965696000,

%U 54064489070592000,1487129136869376000,43312058119249920000

%N a(1)=1; a(n) = n!*Fibonacci(n+2), n > 1.

%C From solution to a difference equation.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Vincenzo Librandi, <a href="/A005922/b005922.txt">Table of n, a(n) for n = 1..200</a>

%H P. R. J. Asveld & N. J. A. Sloane, <a href="/A005442/a005442.pdf">Correspondence, 1987</a>

%H P. R. J. Asveld, <a href="http://www.fq.math.ca/Scanned/25-4/asveld.pdf">Another family of Fibonacci-like sequences</a>, Fib. Quart., 25 (1987), 361-364.

%t Join[{1},Table[n!Fibonacci[n+2],{n,2,20}]] (* _Harvey P. Dale_, May 26 2024 *)

%o (Magma) [1] cat [Factorial(n)*Fibonacci(n+2): n in [2..20]]; // _Vincenzo Librandi_, Jul 10 2012

%o (PARI) a(n)=if(n>1, n!*fibonacci(n+2), 1) \\ _Charles R Greathouse IV_, Jun 30 2017

%Y Cf. A005921, A078700.

%K nonn,easy

%O 1,2

%A _N. J. A. Sloane_

%E More terms and better description from _Vladeta Jovovic_, Jan 23 2005