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The first n-fold intrinsically 7-palindromic number (represented in base 10).
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%I #18 Aug 22 2015 06:06:40

%S 65,186621,3360633

%N The first n-fold intrinsically 7-palindromic number (represented in base 10).

%C Though this sequence is apt to never have many known members, its third is quite a nice coincidence for consideration.

%C A029965 runs just short of space to show it, and A053780 is a totally unrelated collection of palindromes that also includes 33633 in addition to 3360633.

%C a(4) > 10^17. - _Hiroaki Yamanouchi_, Aug 22 2015

%e a(2)=186621 is 3555553 in base 6 and 1405041 in base 7.

%e a(3)=3360633 is 6281826 in base 9 and 1995991 in base 11.

%Y Cf. A171701, A171702, A171703, A171704, A171705, A171741, A029966, A029965, A053780.

%K more,nonn,bref,base

%O 1,1

%A _James G. Merickel_, Dec 16 2009

%E Typo in third term corrected by _James G. Merickel_, Dec 18 2009