There are square pyramidal numbers and tetrahedral numbers, defined(adsbygoogle = window.adsbygoogle || []).push({});

Square pyramidal numbers = n ( n + 1 )( 2 n + 1) / 6

1, 5, 14, 30, 55, 91, 140, 204, 285, 385, 506, 650, ...

Tetrahedral numbers = n ( n + 1 )( n + 2 ) / 6

1, 4, 10, 20, 35, 56, 84, 120, 165, 220, 286, 364, ...

and I was wondering if there's a number(s) besides 1 that is both.

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# Square pyramidal numbers and Tetrahedral numbers

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