7thhexagonalnumber

<-- Enter hexagonal number statement
  

Calculate hexagonal number 7

The formula for hexagonal number n is as follows
Hn = n(2n - 1)

Given n = 7, we have:
Hn = 7(2(7) - 1)
Hn = 7(14 - 1)
Hn = 7(13)
H7 = 91