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%I #6 Oct 04 2020 23:25:23
%S 1,12,13,4,9,9,4,5,6,8,8,6,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,
%T 4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,
%U 2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4,6,4,2,2,4
%N For n>2, a(n) > 0 is such that a(n-1)^2+4*a(n-2)*a(n) is a minimal square, a(1)=1,a(2)=12.
%F a(n)=a(n-5) for n >= 18. - _Robert Israel_, Oct 02 2020
%p A[1]:= 1: A[2]:= 12:
%p for n from 3 to 100 do
%p R:= map(rhs@op, [msolve(y^2=A[n-1]^2, 4*A[n-2])]);
%p ys:= map(t -> (floor((A[n-1]-t)/(4*A[n-2]))+1)*4*A[n-2]+t, R);
%p A[n]:= (min(ys)^2-A[n-1]^2)/(4*A[n-2]);
%p od:
%p seq(A[i],i=1..100); # _Robert Israel_, Oct 02 2020
%Y Cf. A105734 - A105746.
%K nonn
%O 1,2
%A _Zak Seidov_, Apr 19 2005
%E More terms from _Robert Israel_, Oct 02 2020
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