Stella octangula number

In mathematics, a stella octangula number is a figurate number based on the stella octangula, of the form n(2n2 − 1). The sequence of stella octangula numbers is 0, 1, 14, 51, 124, 245, 426, 679, 1016, 1449, 1990, ... (sequence in the OEIS) Only two of these numbers are square.

Stella octangula number

In mathematics, a stella octangula number is a figurate number based on the stella octangula, of the form n(2n2 − 1). The sequence of stella octangula numbers is 0, 1, 14, 51, 124, 245, 426, 679, 1016, 1449, 1990, ... (sequence in the OEIS) Only two of these numbers are square.