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A110811
Perfect powers not a multiple of 10 whose digit reversal is also a perfect power (not necessarily with the same exponent, but with exponent > 1).
2
1, 4, 8, 9, 121, 144, 169, 343, 441, 484, 676, 961, 1089, 1331, 9801, 10201, 10404, 10609, 12321, 12544, 12769, 14641, 14884, 40401, 40804, 44521, 44944, 48841, 69696, 90601, 94249, 96721, 698896, 1002001, 1004004, 1006009, 1022121, 1024144
OFFSET
1,2
COMMENTS
All palindromic perfect powers are trivial members, but there are infinitely many nontrivial members.
LINKS
EXAMPLE
12^2 =144, digit reversal of 144 is 441= 21^2. 12769=113^2, reversal(12769) = 96721 = 311^2.
MATHEMATICA
Join[{1}, Select[Range[11 10^5], Mod[#, 10]!=0&&GCD@@FactorInteger[#][[All, 2]]>1&&GCD@@FactorInteger[IntegerReverse[#]][[All, 2]]>1&]] (* Harvey P. Dale, Jun 01 2018 *)
CROSSREFS
This is a subset of A115656 and also a subset of A001597. See also A118895 to include terms with trailing zeros.
Sequence in context: A217700 A118895 A327654 * A226035 A128827 A075786
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Aug 15 2005
EXTENSIONS
Corrected and extended by Joshua Zucker, May 04 2006
Description and offset edited by Chai Wah Wu, Jun 06 2016
STATUS
approved