What was the smallest 5-digit star number?

Here are the first few star numbers: 1, 13, 37, 73, 121, 181, 253, 337, 433, 541, 661, 793, 937, 1093, 1261, 1441, 1633, 1837, 2053, 2281, 2521, 2773, 3037, 3313, 3601, 3901, 4213, 4537, 4873, 5221, 5581, 5953, 6337, 6733, 7141, 7561, 7993, 8437, 8893, 9361, 9841, 10333, 10837,... As you can see the smallest 5 digit one is 5221. For any natural number n, the nth star number can be found from this formula. 6n(n - 1) + 1 For those who do not know, a star number is a figurate number that is a centered hexagram. It looks like a Chinese checker board, if you ever played that. Dr. Chuck