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The first 3-fold intrinsically n-palindromic number (given in base ten).
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%I #15 Aug 22 2015 06:34:51

%S 18,154,19040,267140,2853326516320,3360633

%N The first 3-fold intrinsically n-palindromic number (given in base ten).

%C The large value for the 6-palindrome case, a(6)=2853326516320, has 139 as the smallest of the three bases.

%C 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.

%C a(8) > 10^18. - _Hiroaki Yamanouchi_, Aug 22 2015

%e a(5)=267140 is 6D4D6 in base 14, 54245 in base 15, and 29E92 in base 18.

%e a(7)=3360633 is 6281826 in base 9 and 1995991 in base 11.

%Y Cf. A171701, A171702, A171703, A171704, A171705, A171706, A171740, A171742, A053780, A029966, A029965.

%K nonn,more,base

%O 2,1

%A _James G. Merickel_, Dec 17 2009