Awesome, beautiful really. I'm really into numbers. My birthday added up=33 could explain my obsession with the great Nikola Tesla? I'm told its rare for birthdays sum up to 33. Interesting stuff.
I'd thought about it, I'm not a maths kinda person, so don't laugh.
3-6-9 repeats when multiplying by divine threes. You get into the double digits, add those so they're singular. 12=3 15=6 18=9 21=3 24=6 27=9 forever repeats that way.