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a(n) = n^2*a(n-1)+1, a(1)=0.
1

%I #10 Feb 19 2014 15:53:12

%S 0,1,10,161,4026,144937,7101914,454522497,36816322258,3681632225801,

%T 445477499321922,64148759902356769,10841140423498293962,

%U 2124863523005665616553,478094292676274763724426

%N a(n) = n^2*a(n-1)+1, a(1)=0.

%H Harvey P. Dale, <a href="/A074703/b074703.txt">Table of n, a(n) for n = 1..253</a>

%F a(n) = round(n!^2*(BesselI(0, 2)-2)).

%t nxt[{n_,a_}]:={n+1,(n+1)^2 a+1}; Transpose[NestList[nxt,{1,0},20]][[2]] (* _Harvey P. Dale_, Dec 11 2013 *)

%o (PARI) a(n)=round((besseli(0,2)-2)*n!^2) \\ _Charles R Greathouse IV_, Feb 19 2014

%Y Cf. A006040, A073701.

%K easy,nonn

%O 1,3

%A _Vladeta Jovovic_, Sep 03 2002