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%I #14 Jul 18 2021 06:47:42
%S 70,79822843,69852478553064869297984899963805,
%T 77473062193002372448027740546437,77747359197583788609974143907617,
%U 84341826458653210947638195982113,85367942837521291760016984490249
%N Numbers k such that k*(k+5) gives the concatenation of two numbers m and m-2.
%e 79822843 * 79822848 = 63716866//63716864, where // denotes concatenation.
%Y Cf. A028557, A116107, A116268, A116275, A116277, A116281.
%K nonn,base
%O 1,1
%A _Giovanni Resta_, Feb 06 2006