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A117784
Total number of palindromic primes in base 7 with n digits.
1
3, 0, 6, 0, 41, 0, 154, 0, 931, 0, 4951, 0, 29932, 0, 180914, 0, 1089138, 0, 6823068, 0, 43644808, 0, 274927477, 0
OFFSET
1,1
COMMENTS
Every palindrome with an even number of digits is divisible by 11 (in base 7) and therefore is composite (not prime). Hence there is no palindromic prime with an even number of digits.
CROSSREFS
Sequence in context: A352610 A307644 A081978 * A257896 A268978 A280585
KEYWORD
nonn,base
AUTHOR
Martin Renner, Apr 15 2006
EXTENSIONS
a(9)-a(24) from Chai Wah Wu, Dec 26 2015
STATUS
approved