A216786 - OEIS

%I #12 Jan 03 2021 14:08:26

%S 1,110,12705,1490720,176277640,20941783632,2495562549480,

%T 298041470195040,35653210872081660,4270462368900447720,

%U 512028438031163681628,61443412563739641795360,7378329792029068652259480,886534702703800402679177520,106574136046464005550646840440

%N a(n) = Product_{k=1..n} (121 - 11/k).

%C This sequence is generalizable: Product_{k=1..n} (q^2 - q/k) = (q^n/n!) * Product_{k=0..n-1} (q*k + q-1) = expansion of (1- x*q^2)^((1-q)/q).

%p seq(product(121-11/k, k=1.. n), n=0..20);

%p seq((11^n/n!)*product(11*k+10, k=0.. n-1), n=0..20);

%p A216786 := proc(n)

%p     binomial(-10/11,n)*(-121)^n ;

%p end proc: # _R. J. Mathar_, Sep 17 2012

%t Join[{1},FoldList[Times,121-11/Range[20]]] (* _Harvey P. Dale_, Mar 15 2016 *)

%Y Cf. A004988, A049382, A004994, A216702, A216703, A216704, A216705, A216706.

%K nonn

%O 0,2

%A _Michel Lagneau_, Sep 16 2012