Tetrahedral numbers - Math Central

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Question from rena, a parent:

consider the tetrahedral numbers 1,4,10,20, etc. Can these numbers be
described as a polynomial? If so, what is the degree of that polynomial?

Hi Rena. The nth tetrahedral number can be found using the expression

n(n+1)(n+2) / 6.

What degree is this polynomial?

Hope this helps.
Stephen La Rocque.

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