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%I #3 Mar 30 2012 17:34:19
%S 0,2,10,92,1320,25664,628400,18544032,640243520,25313036288,
%T 1127562249600,55871851754240,3048145476992000,181547804177418240,
%U 11721355489130393600,815411545722159841280,60804225264488076288000
%N a(n) = 5*(n-1)*a(n-1) -2*(n-1)*a(n-2) with a(0)=0, a(1)=2.
%C This is also the negative of the (1,2) element of the product matrix after multiplying the unit matrix from the
%C left by the matrices (0,-2;j-1,5j-5) in the order j=2 to n.
%t M[n_] := {{0, -2}, {(n - 1), 5*(n - 1)}} v[1] = {0, 1} v[n_] := v[n] = M[n].v[n - 1] a = Table[Abs[v[n][[1]]], {n, 1, 25}]
%Y Cf. A000166.
%K nonn,easy
%O 0,2
%A _Roger L. Bagula_, Jun 15 2005
%E Definition replaced by recurrence by the Associate Editors of the OEIS, Sep 28 2009
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