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 A131760 Numbers n such that n multiplied by its reverse yields a fourth power. 1
 1, 4, 9, 121, 484, 676, 2178, 8712, 10000, 10201, 12321, 14641, 40000, 40804, 44944, 69696, 90000, 94249, 698896, 1002001, 1210000, 1234321, 4008004, 4840000, 5221225, 6760000, 6948496, 21780000, 87120000, 100000000, 100020001 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence contains palindromic squares and palindromic squares with trailing zeros. Are 2178 and 8721 the only non-palindromic reversible pair in this sequence without trailing zeros? LINKS Chai Wah Wu, Table of n, a(n) for n = 1..108 EXAMPLE 2178 = 2*9*121 and 8712 = 8*9*121, 2718*8712 = (2*3*11)^4. MATHEMATICA Select[Range[1000000], IntegerQ[(#*FromDigits[Reverse[IntegerDigits[ # ]]])^(1/4)] &] CROSSREFS Cf. A002779 = Palindromic squares. Sequence in context: A115667 A229971 A158642 * A002779 A028817 A319483 Adjacent sequences:  A131757 A131758 A131759 * A131761 A131762 A131763 KEYWORD nonn,base AUTHOR Tanya Khovanova, Sep 17 2007 EXTENSIONS a(20)-a(31) from Donovan Johnson, Oct 27 2008 STATUS approved

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Last modified December 16 00:55 EST 2018. Contains 318157 sequences. (Running on oeis4.)