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%I #12 May 30 2015 11:02:23
%S 2,3,8,32,160,960,6720,53760,483840,4838400,53222400,638668800,
%T 8302694400,116237721600,1743565824000,27897053184000,474249904128000,
%U 8536498274304000,162193467211776000,3243869344235520000
%N a(1)=2; a(n)=ceiling(n*(a(n-1)-1/a(n-1))).
%F a(1)=2 a(2)=3 and for n>2, a(n)= 4*n!/3.
%F a(n) = A090802(n, n-3) for n > 2. - _Ross La Haye_, Sep 26 2005
%t nxt[{n_,a_}]:={n+1,Ceiling[(n+1)(a-1/a)]}; Transpose[NestList[nxt,{1,2},20]][[2]] (* _Harvey P. Dale_, May 30 2015 *)
%Y Equals 4 * A002301.
%K nonn
%O 1,1
%A _Benoit Cloitre_, May 06 2003