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%I #12 Jun 22 2022 11:05:48
%S 2,3,7,46,2112,4460539,19896408170515,395867058087736049315365218,
%T 156710727679038987453730700439845485538142584724187516
%N a(1) = 2, a(n+1) = a(n)^2 - n.
%C The next term -- a(10) -- has 107 digits. - _Harvey P. Dale_, Jun 22 2022
%H MathOverflow, <a href="http://mathoverflow.net/questions/147217/asymptotic-behavior-of-the-sequence-u-n-u-n-12-n">Asymptotic behavior of the sequence u(n) = u(n-1)^2 - n</a>
%t RecurrenceTable[{a[1]==2,a[n+1]==a[n]^2-n},a,{n,10}] (* _Harvey P. Dale_, Jun 22 2022 *)
%o (PARI) vector(10,k,t=if(k==1,2,t^2-(k-1)))
%Y Cf. A086051.
%K nonn,easy
%O 1,1
%A _Franklin T. Adams-Watters_, Nov 01 2011