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%I #7 Dec 24 2014 12:13:47
%S 1,2,5,23,455,197447,38895873863,1512881323770591465287,
%T 2288809899755012359449577849239960517955399,
%U 5238650757216549725917660910593720468102050623548424798300898740084824366637074960199
%N a(n+1) = smallest number that is not the sum of a(n) or fewer terms of a(1),...,a(n).
%F a(n+1)=a(n)^2+2*a(n)-a(n)*a(n-1)-a(n-1), n>1.
%t RecurrenceTable[{a[1]==1,a[2]==2,a[n]==a[n-1]^2+2a[n-1]- a[n-1] a[n-2]- a[n-2]},a,{n,10}] (* _Harvey P. Dale_, Dec 24 2014 *)
%K nonn
%O 1,2
%A _Erich Friedman_
%E Formula and more terms from _Christian G. Bower_.