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%I #7 Jul 18 2021 02:55:19
%S 27,71,79822844,69852478553064869297984899963806,
%T 77473062193002372448027740546438,77747359197583788609974143907618,
%U 84341826458653210947638195982114,85367942837521291760016984490250
%N Numbers k such that k*(k+3) gives the concatenation of two numbers m and m+2.
%e 79822844 * 79822847 = 63716866//63716868, where // denotes concatenation.
%Y Cf. A116171, A116296, A116301, A116303, A116309.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 06 2006