A116239 Numbers k such that k*(k+8) gives the concatenation of two numbers m and m-8.
7743, 8017, 33294314, 66705679, 98000197, 340465755421, 476452552741, 523547447252, 659534244572, 866013200677, 998000001997, 3695104677080130, 3755782995538764, 4198081170077527, 4803478892324962, 5196521107675031
Offset: 1
Examples
98000197 * 98000205 = 96040393//96040385, where // denotes concatenation.