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# Monthly Archives: December 2006

## Computing tetrahedral numbers

I left off the discussion of tetrahedral numbers in my last post by posing the question of what the 144th tetrahedral number is, and promising to explain a quick way to figure it out without having to actually add up … Continue reading

Posted in computation, famous numbers, geometry, sequences
3 Comments

## The Twelve Days of Christmas and Tetrahedral Numbers

(Edit, 12/5/07: I guess it’s that time of year again, isn’t it? =) I’ve started to see a lot more traffic to this post in the last few days. For anyone finding me through a Google search, I wanted to … Continue reading

Posted in famous numbers, games, geometry, sequences
17 Comments