A352947 Prime numbers representing a date based on the proleptic Gregorian calendar in YY..YMMDD format.

10103, 10111, 10211, 10223, 10301, 10303, 10313, 10321, 10331, 10427, 10429, 10501, 10513, 10529, 10531, 10601, 10607, 10613, 10627, 10709, 10711, 10723, 10729, 10831, 10903, 10909, 11003, 11027, 11113, 11117, 11119, 11213, 20101, 20107, 20113, 20117, 20123

Offset: 1

Author

Ya-Ping Lu, Apr 10 2022

Keywords

• nonn
• base

Examples

			20050403 is a term because the date 'Apr 3, 2005' represented in YY..YMMDD format is 20050403, which is a prime number.
		

Crossrefs

Cf. A227407, A227409, A354422.

Programs

Python

from sympy import isprime
for y in range(1, 3):
    for m in range(1, 13):
        d_max = 31 if m in {1, 3, 5, 7, 8, 10, 12} else 30 if m in {4, 6, 9, 11} else 28 if (y%4 or (y%400 and not y%100)) else 29
        for d in range(1, d_max + 1):
            date = 10000*y + 100*m + d
            if isprime(date): print(date, end = ', ')