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A171741
The first 3-fold intrinsically n-palindromic number (given in base ten).
24
18, 154, 19040, 267140, 2853326516320, 3360633
OFFSET
2,1
COMMENTS
The large value for the 6-palindrome case, a(6)=2853326516320, has 139 as the smallest of the three bases.
Coincidentally, the following much shorter term, a(7)= 3360633, involves base 9 through 11, the conjunction of base-9 and base-10 palindromes (A029965) comes up a term short (assuming space limitations remain as they are at the beginning of 2011), and A053740 is a totally unrelated collection of palindromes that also contains 33633.
a(8) > 10^18. - Hiroaki Yamanouchi, Aug 22 2015
EXAMPLE
a(5)=267140 is 6D4D6 in base 14, 54245 in base 15, and 29E92 in base 18.
a(7)=3360633 is 6281826 in base 9 and 1995991 in base 11.
KEYWORD
nonn,more,base
AUTHOR
James G. Merickel, Dec 17 2009
STATUS
approved