

A062352


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


6



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
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

The last term of this finite series is 97654321012345679.


LINKS



EXAMPLE

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.


PROG

(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()))


CROSSREFS



KEYWORD

nonn,base,fini,full


AUTHOR



EXTENSIONS



STATUS

approved



