871 = 16 Sum = 7 Root

1 + 6 = 7 Root

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312 = 06 Sum = 6 Root

000 = 00 Sum = 0 Root

162 = 09 Sum = 9 Root

999 = 27 Sum = 9 Root

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There are 10 Roots from 0 up to 9

All the 10 Roots = 1000 Straight and 220 Box Numbers.

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Pairs:

93 = 12 Sum = 3 Root

00 = 00 Sum = 0 Root

99 = 18 Sum = 9 Root

There are 19 Sums for the Pairs.

There are 10 Roots.

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