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a(n) = a(n-1)! + a(n-2)!.
2

%I #10 Mar 03 2023 23:13:14

%S 1,1,2,3,8,40326

%N a(n) = a(n-1)! + a(n-2)!.

%C The next term has 168215 decimal digits. - _Rick L. Shepherd_, Nov 04 2004

%t nxt[{a_,b_}]:={b,a!+b!}; NestList[nxt,{1,1},5][[All,1]] (* _Harvey P. Dale_, Aug 12 2020 *)

%Y A114020 is an essentially identical sequence.

%K nonn,easy

%O 0,3

%A _N. J. A. Sloane_.