08-Jan-2013, 10:43 AM
Quote:... How?You add the two numbers, then add 1 if the next numbers add to something above 9
:
618 970 019 642 690 137 449 562 112
+
618 970 019 642 690 137 449 562 112
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: 1 237 940 039 285 380 274 899 124 224