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A117780 Total number of palindromic primes in base 5 with n digits. 1
2, 0, 5, 0, 18, 0, 58, 0, 160, 0, 795, 0, 3167, 0, 13519, 0, 60829, 0, 270693, 0, 1177412, 0, 5502114, 0, 25026242, 0, 114884910, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Every palindrome with an even number of digits is divisible by 11 (in base 5) and therefore is composite (not prime). Hence there is no palindromic prime with an even number of digits.
LINKS
Eric Weisstein: Palindromic Prime.
CROSSREFS
Sequence in context: A260330 A094032 A261044 * A155759 A202209 A201730
KEYWORD
nonn,base
AUTHOR
Martin Renner, Apr 15 2006
EXTENSIONS
a(11)-a(28) from Chai Wah Wu, Dec 27 2015
STATUS
approved

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Last modified March 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)