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A171704
The first n-fold intrinsically 5-palindrome (represented in base ten).
25
17, 2293, 267140, 4838419019
OFFSET
1,1
COMMENTS
The fourth term, which is first 5-palindromic in base 91, is almost a concatenation of base-ten 5-palindromes.
A217146 gives the sequence of values 5-palindromic in at least 4 bases. The search there indicates a fifth term here has first base of 5-palindromicity above 200. - James G. Merickel Oct 19 2012
a(5) > 10^14. - Hiroaki Yamanouchi, Aug 22 2015
EXAMPLE
a(2)=2293 is 33133 in base 5 and 14341 in base 6;
a(3)=267140 is 6D4D6, 54245 and 29E92 in bases 14, 15 and 18, respectively.
KEYWORD
nonn,more,base
AUTHOR
James G. Merickel, Dec 17 2009
STATUS
approved