%I #14 Jul 11 2024 21:43:40
%S 0,1,3,1,-17,-2719,-33231617,-1990664248298239,
%T 825155821714086784897292716543,
%U -6468873315977272230111786035347284128217298704834756326835199
%N Let x(1) = 1 and x(n) = x(n-1)^2 + i for n>1; a(n) is the imaginary part of x(n).
%F a(n+1) = 2*a(n)*A143848(n) + 1.
%e The x(n) sequence starts 1, 1+i, 3*i, -9+i, 80-17*i, 6111-2719*i, ...
%Y A143848 gives the read part of x(n).
%K sign
%O 1,3
%A _Reinhard Zumkeller_, Sep 03 2008
%E Definition clarified by _N. J. A. Sloane_, Jul 11 2024 at the suggestion of _Harvey P. Dale_.