The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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 (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 7) 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: 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

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 16 11:24 EDT 2024. Contains 372552 sequences. (Running on oeis4.)