ARSE

Sat 18 Aug 2018

Centred Triangular Prime Days

Enter your date of birth.
Find out when you will be celebrating!

A centred triangular prime is a centred triangular number that is prime.

Centred triangular numbers are of the form
**(3n ^{2} + 3n + 2) / 2**

A centred triangular number is a centred figurate number that represents a triangle with a dot in the centre and all other dots surrounding the centre in successive triangular layers.

The figures for the first four centred triangular numbers are shown below: