# Tetrahedral number Calculator

## Calculates the number of balls and the height in a regular tetrahedron.

 number of stages 1,2,3,... 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit total balls Tn height to accumulate hn ( diameter of a ball =1 )
 $\normal Tetrahedral\ number\\\vspace{5}(1)\ total\ balls\\\hspace{40} T_n={\large\sum_{\small k=1}^n\frac{k(k+1)}{2}}={\large\frac{n(n+1)(n+2)}{6}}\\[10](2)\ height\ to\ accumulate\\\hspace{40} h_n=\sqrt{\large\frac{2}{3}}(n-1)+1\\$
Tetrahedral number
 [1-1] /1 Disp-Num5103050100200
[1]  2018/05/05 04:47   Female / Under 20 years old / Elementary school/ Junior high-school student / Useful /
Purpose of use
Ping-Pong ball packaging project
Comment/Request
Please make changing the diameter an option.

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