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%I #5 Jan 04 2021 18:18:00
%S 4622,5377,7980,34952,46865,53134,65047,7056186,9783459,43176670,
%T 56823329,97999800,447255476452,552744523547,755424659534,
%U 799319866013,997999998000,4297663349523,5702336650476,6971253996227
%N n times n+2 gives the concatenation of two numbers m and m-9.
%H Robert Israel, <a href="/A116226/b116226.txt">Table of n, a(n) for n = 1..1122</a>
%e 97999800 * 97999802 = 96039609//96039600, where // denotes
%e concatenation.
%p A:= NULL: count:= 0:
%p for d from 2 to 40 do
%p R:= [msolve(x^2=-8,10^d+1)];
%p T:= sort(select(t -> t*(t+2) mod 10^d >= 10^(d-1), map(t -> subs(t,x-1),R)));
%p count:= count+nops(T);
%p A:= A, op(T);
%p od:
%p A; # _Robert Israel_, Jan 04 2021
%Y Cf. A116095, A116225, A116227, A116233.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 06 2006