A062352 Palindromic primes with strictly decreasing digits up to the middle and then strictly increasing.

2, 3, 5, 7, 11, 101, 313, 727, 757, 919, 929, 31013, 73037, 73237, 74047, 76367, 91019, 93139, 93239, 94049, 94349, 96269, 96469, 97379, 97579, 98389, 98689, 7310137, 7521257, 7540457, 7630367, 7632367, 7654567, 9320239, 9610169

Offset: 1

Author

Amarnath Murthy, Jun 23 2001

Keywords

• nonn
• base
• fini
• full

Comments

The last term of this finite series is 97654321012345679.

There are 84 terms. - Michael S. Branicky, Aug 04 2022

Examples

			31013 belongs to the sequence as it is a palindromic prime in which the digits are decreasing up to the middle digit 0 and then increasing.
		

Links

• Michael S. Branicky, Table of n, a(n) for n = 1..84 (full sequence)
• Patrick De Geest, World of Palindromic Primes

Crossrefs

Cf. A062351.

Programs

Python

from sympy import isprime
from itertools import combinations
def bgen():
    for digits in range(1, 20):
        for left in combinations("9876543210", (digits+1)//2):
            left = "".join(left)
            yield int(left + (left[:digits//2])[::-1])
afull = sorted(filter(isprime, bgen()))
print(afull) # Michael S. Branicky, Aug 04 2022

Extensions

Corrected and edited by Patrick De Geest, Jun 07 2003