Hexagonal pyramidal number

A hexagonal pyramidal number is a number formed by adding the first few hexagonal numbers. The first few numbers are:

1, 7, 22, 50, 95, 161, 252, 372, 525, 715, 946, 1222, 1547, 1925 (sequence A002412 in OEIS)

The numbers have the form:

${n(n+1)(4n-1)}\over6$

[edit] References

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