A115436 - OEIS

%I #5 Jul 15 2021 06:23:08

%S 50,5234,9410,638370,994010,12477933,41829698,99940010,1087279650,

%T 4492494893,6226356365,7765453730,9999400010,806057802450,

%U 842377434050,960398039610,999994000010,21338126513658,24752544267698

%N Numbers k such that the concatenation of k with k-9 gives a square.

%e 638370_638361 = 798981^2.

%Y Cf. A030465, A102567, A115426, A115437, A115428, A115429, A115430, A115431, A115432, A115433, A115434, A115435, A115447.

%K base,nonn

%O 1,1

%A _Giovanni Resta_, Jan 25 2006