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A171706
The first n-fold intrinsically 7-palindromic number (represented in base 10).
25
65, 186621, 3360633
OFFSET
1,1
COMMENTS
Though this sequence is apt to never have many known members, its third is quite a nice coincidence for consideration.
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.
a(4) > 10^17. - Hiroaki Yamanouchi, Aug 22 2015
EXAMPLE
a(2)=186621 is 3555553 in base 6 and 1405041 in base 7.
a(3)=3360633 is 6281826 in base 9 and 1995991 in base 11.
KEYWORD
more,nonn,bref,base
AUTHOR
James G. Merickel, Dec 16 2009
EXTENSIONS
Typo in third term corrected by James G. Merickel, Dec 18 2009
STATUS
approved