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A113800 Numbers n such that n^2 plus the reverse of n^2 gives a perfect power. 0
2, 231, 1010, 102010, 451429, 1000100, 9426681 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

451429^2 = 203788142041 and 203788142041+140241887302=7007^3,

9426681^2 = 88862314675761 and 88862314675761+16757641326888=10277157^2.

MATHEMATICA

ppQ[n_] := n != 1 && GCD @@ (Transpose[FactorInteger[n]][[2]]) > 1; rev[n_] := FromDigits@Reverse@IntegerDigits@n ; lst = {}; Do[If[ppQ[n^2 + rev[n^2]], AppendTo[lst, n]], {n, 10^6}]; lst

CROSSREFS

Sequence in context: A071225 A015968 A095220 * A133495 A066622 A012671

Adjacent sequences:  A113797 A113798 A113799 * A113801 A113802 A113803

KEYWORD

base,nonn

AUTHOR

Giovanni Resta (g.resta(AT)iit.cnr.it), Jan 22 2006

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Last modified February 17 03:45 EST 2012. Contains 205978 sequences.