For how many integers having between 1 and 10 digits (base 10) are all of their digits when read from left to right monotonically increasing? In other words, every digit is less than or equal to all of those to its right. For example, 244467889 is one of them, and 0 is another, but there are more.
(In reply to re: found the mapping
by Steve Herman)
I had a very busy day, and wanted to post a detailed description of one-to-one mapping of the mon. increasing numbers into a binary string of 19 bits later in the evening..
I liked the problem very much, still I really feel getting a prize (extra time) on the last day of the year by virtue of someone releasing the
method which I found independently, - who cares about "credits"..
and Happy New Year to all.