Otis
Elite Member
- Joined
- Apr 22, 2015
- Messages
- 4,414
Oh for Pete's sake. I'd been counting distinct p's and q's, not ordered pairs!
This is the fourth thread I've misread/mangled in a week. I must need time off.
Anyway, the pattern 1,1,2,2,3,3,...,9,9 adds up to 90, plus the 19 multiples of 5 below 99 makes 109.
[imath]\;[/imath]
This is the fourth thread I've misread/mangled in a week. I must need time off.
Anyway, the pattern 1,1,2,2,3,3,...,9,9 adds up to 90, plus the 19 multiples of 5 below 99 makes 109.
[imath]\;[/imath]