30 Mar
2020
30 Mar
'20
10:08 a.m.
KFL: "What do 3076521984, 3718250496, and 6398410752, and no other numbers, have in common?" They are obviously pandigital numbers and thus share the divisor 3^2. The GCD of the three numbers divided by 9 is a large power of 2. A quick check shows that no other pandigital has that large a power-of-two divisor (the next largest being for 9805234176).