A Little NUmber Curiosity
Posted: Fri Apr 30, 2010 12:11 pm
Recently, I was doing some number crunching that involved 9 and multiples thereof. Just for fun, look at the digits for the INVERSE of each of these numbers. The "special properties" (whatever that might mean) of 9 have been studied and used since ancient times.
In the numbers below, they mostly show insertion of zeros. But the set begining with 81 runs a bit differently by inserting various digits. And it appears 81*9 =729 contiunes with the insertion of digits. I didn't pursue this one further.
I'm sure those of you that are pattern finders will see also that the sum of the digits reduce to 9.
Also, why don't ALL numbers that reduce to 9 give these "unusual" sequences? For example, 27 doesn't produce a very "pleasing" sequences of digits.
9, 99, 999, 9999, ...
18, 1818, 181818, ...
45, 4545, 454545, ...
36, 3636, 363636, ...
81, 8181, 818181, 81818181, ...
108, 108108, 108108108, ...
81*9 = 729
DrDave
In the numbers below, they mostly show insertion of zeros. But the set begining with 81 runs a bit differently by inserting various digits. And it appears 81*9 =729 contiunes with the insertion of digits. I didn't pursue this one further.
I'm sure those of you that are pattern finders will see also that the sum of the digits reduce to 9.
Also, why don't ALL numbers that reduce to 9 give these "unusual" sequences? For example, 27 doesn't produce a very "pleasing" sequences of digits.
9, 99, 999, 9999, ...
18, 1818, 181818, ...
45, 4545, 454545, ...
36, 3636, 363636, ...
81, 8181, 818181, 81818181, ...
108, 108108, 108108108, ...
81*9 = 729
DrDave