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Smallest palindromic number of length 17 in two bases differing by n.
15

%I #19 Jul 24 2015 07:28:04

%S 1939137135947326,8535888851411555386,670814726929288547601

%N Smallest palindromic number of length 17 in two bases differing by n.

%C 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.

%e The second term, 8535888851411555386 in decimal, is CA9BB36AAA63BB9AC in base 13 and is 1475E0C2C2C0E5741 in base 15 (employing the notation standard for hexadecimal).

%Y Multi-base palindrome records: A171701, A171702, A171703, A171704, A171705, A171706, A171740, A171741, A171742, A171775.

%Y Others in this collection: A216840, A216841, A216843, A216899, A216900, A216901, A216902, A216903, A216904, A216905, A216906, A216907, A216908, A216909.

%K nonn,base,bref

%O 1,1

%A _James G. Merickel_, Sep 19 2012