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A216910
Smallest palindromic number of length 17 in two bases differing by n.
15
1939137135947326, 8535888851411555386, 670814726929288547601
OFFSET
1,1
COMMENTS
Smallest of pair of bases are 8, 13, 17. The 16-palindrome case for this collection of sequences only has the n=2 example--bases are 13 and 15--530386561769238496 as of the time of this submission (hence, no sequence for that length). A 1st term for 19-palindromes is also available. It is the even semiprime 6411682614162861146, which reads as 11759A6746476A95711 in base 11. See A216840 and A216841 for comments pertaining to entire collection of sequences.
EXAMPLE
The second term, 8535888851411555386 in decimal, is CA9BB36AAA63BB9AC in base 13 and is 1475E0C2C2C0E5741 in base 15 (employing the notation standard for hexadecimal).
CROSSREFS
KEYWORD
nonn,base,bref
AUTHOR
James G. Merickel, Sep 19 2012
STATUS
approved