A115689 Powerful(1) numbers (A001694) whose digit reversal is a square.

1, 4, 9, 100, 121, 144, 169, 400, 441, 484, 675, 676, 900, 961, 1000, 1089, 1800, 4000, 9000, 9801, 10000, 10201, 10404, 10609, 12100, 12321, 12544, 12769, 14400, 14641, 14884, 16900, 18000, 18252, 40000, 40401, 40804, 44100, 44521, 44944

Offset

1,2

Links

Harvey P. Dale, Table of n, a(n) for n = 1..160

Index entries for sequences related to powerful numbers

Example

18252=2^2*3^3*13^2 is powerful and 25281=159^2.

Mathematica

Join[{1}, Select[Range[50000], Min[FactorInteger[#][[All, 2]]]>1&& IntegerQ[ Sqrt[ IntegerReverse[#]]]&]] (* Harvey P. Dale, Aug 08 2020 *)

Crossrefs

Cf. A001694, A115690.

Sequence in context: A247009 A245241 A115690 * A061457 A069707 A129967

Adjacent sequences: A115686 A115687 A115688 * A115690 A115691 A115692

Keyword

nonn,base

Author

Giovanni Resta, Jan 31 2006

Status

approved