Triangular numbers: Difference between revisions

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In general, these all belong to the class [[wp:Figurate_number|figurate numbers]] as they are
In general, these all belong to the class [[wp:Figurate_number|figurate numbers]] as they are
based on '''r''' dimensional geometric figures. Sometimes they are referred to as '''r-simplex'''
based on '''r''' dimensional geometric figures. Sometimes they are referred to as '''r-simplex'''
numbers. In geometry a [[wp:Simplex|simplex]] is the simplest '''r-dimensional'''
numbers. In geometry a [[wp:Simplex|simplex]] is the simplest possible '''r-dimensional'''
object possible.
object.


You may easily extend to an arbitrary dimension '''r''' using binomials. Each term '''n''' in dimension '''r''' is <math>r_n = \binom{n + r - 1}{r}</math>
You may easily extend to an arbitrary dimension '''r''' using binomials. Each term '''n''' in dimension '''r''' is <math>r_n = \binom{n + r - 1}{r}</math>


There is no known general formula to find roots of higher r-simplex numbers.
There is no known general formula to find higher r-simplex roots.