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A171703
The first n-fold intrinsically 4-palindromic number (represented in base ten).
24
9, 624, 19040, 30222192, 592704000, 12040481088, 128024064000, 1024192512000, 3456649728000
OFFSET
1,1
COMMENTS
The fifth and sixth terms are both cubes, exploiting the simple binomial expansion as (m)(m)^3=(m^3)(3m^3)(3m^3)(m^3) for much of their status. - James G. Merickel, Dec 19 2009
The first base in which the fifth term is 4-palindromic is 209. - James G. Merickel, Dec 18 2009
a(10) <= 27653197824000, a(11) <= 27653197824000, a(12) <= 575100098496000, a(13) <= 1733189185728000, a(14) <= 1733189185728000, a(15) <= 8400090327552000. - Hiroaki Yamanouchi, Sep 24 2014
EXAMPLE
a(2)=624 is 4444 in base 5 and 1551 in base 7.
KEYWORD
nonn,base
AUTHOR
James G. Merickel, Dec 16 2009
EXTENSIONS
a(5)-a(6) from James G. Merickel, Dec 19 2009
a(7)-a(9) from Hiroaki Yamanouchi, Sep 24 2014
STATUS
approved