%I #28 Jun 16 2021 10:51:37
%S 1,1,1,2,3,8,10,36,21,216,-126,1960,-3751,25044,-74230,403144,
%T -1489095,7638000,-32168046,164287728,-756314855,3929115500,
%U -19332654222,103079467832,-535020703583,2937890929320,-15952504285350,90295702455504,-510040670796063,2974949788743940
%N a(n) = (n - 1)*(a(n - 2) - a(n - 3) + 1), a(0) = a(1) = a(2) = 1.
%H G. C. Greubel, <a href="/A121989/b121989.txt">Table of n, a(n) for n = 0..450</a> [offset shifted by _Georg Fischer_, Jun 16 2021]
%F a(n) ~ -(-1)^n * c * exp(sqrt(n) - n/2) * n^(n/2 - 1/2), where c = 0.129033591674598655926361807738303723517665374090153324757335... - _Vaclav Kotesovec_, Jun 16 2021
%t RecurrenceTable[{a[0]==a[1]==a[2]==1,a[n]==(n-1)a[n-2]-(n-1)a[n-3]+ n-1}, a,{n,0,30}] (* _Harvey P. Dale_, Dec 08 2011 *)
%K sign,easy
%O 0,4
%A _Roger L. Bagula_, Sep 11 2006
%E Edited by _N. J. A. Sloane_, Sep 24 2006
%E Offset changed to 0 by _Georg Fischer_, Jun 16 2021
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