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A156316 Perfect squares with property that their digit reversal is a larger perfect square. 1
144, 169, 1089, 10404, 10609, 12544, 12769, 14884, 1004004, 1006009, 1022121, 1024144, 1026169, 1042441, 1044484, 1062961, 1214404, 1216609, 1236544, 1238769, 1256641, 1258884, 1444804, 1468944, 4048144, 4088484, 10036224 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A061457. - R. J. Mathar, Feb 08 2009

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..399

EXAMPLE

a(1)=144 because the digit reverse of 144 is 441, which is the square of 21.

MAPLE

read("transforms") ; for n from 1 to 20000 do n2 := n^2 ; n2r := digrev(n2) ; if issqr(n2r) and n2r > n2 then printf("%d, ", n2) ; fi; od: # R. J. Mathar, Feb 08 2009

MATHEMATICA

drlpsQ[n_]:=Module[{rev=FromDigits[Reverse[IntegerDigits[n]]]}, rev>n && IntegerQ[ Sqrt[rev]]]; Select[Range[3200]^2, drlpsQ] (* Harvey P. Dale, Jan 15 2015 *)

CROSSREFS

Sequence in context: A062917 A035090 A064021 * A323614 A245214 A257412

Adjacent sequences:  A156313 A156314 A156315 * A156317 A156318 A156319

KEYWORD

nonn,base

AUTHOR

Gaurav Kumar, Feb 07 2009

EXTENSIONS

More terms from R. J. Mathar and Gaurav Kumar, Feb 08 2009

STATUS

approved

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Last modified October 23 23:51 EDT 2019. Contains 328379 sequences. (Running on oeis4.)