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A tedious puzzle (but not homework)
There was this question on a show called "Growing Pains Of a Teenage Genius"
The question is as follows:
- 1000 coins are lined up, heads up
oooooooooooooooooooooooooooooooooooo...
and every 2nd coin is flipped over to tails
o•o•o•o•o•o•o•o•o•o•o•o•o•o•o•o•o•o•...
then every 3rd coin is flipped over again
o•••ooo•••ooo•••ooo•••ooo•••ooo•••oo...
and so on, until every 1000th coin.
What coins remain as heads?