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A207373 Numbers whose square is the product of a number and its reverse. 1
252, 403, 504, 660, 816, 2772, 3267, 4356, 20502, 22932, 23632, 25452, 26962, 27972, 31003, 32967, 35143, 41004, 43956, 45864, 48384, 48616, 55242, 58422, 66976, 75525, 225522, 252252, 259952, 279972, 329967, 341033, 403403, 439956, 451044, 504504, 619916 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number and its reverse must have the same number of digits.

Number squared cannot be a palindrome. - Harvey P. Dale, Mar 12 2017

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..90

EXAMPLE

35143^2 = 96721*12769.

MATHEMATICA

nir[n_]:=If[PalindromeQ[n]||Divisible[n, 10], 0, n IntegerReverse[n]]; Sqrt[#] &/@ Select[Array[nir, 500000], #!=0&&IntegerQ[Sqrt[#]]&]//Union (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Mar 12 2017 *)

CROSSREFS

Cf. A076750.

Sequence in context: A046331 A066695 A104396 * A072443 A129623 A062904

Adjacent sequences:  A207370 A207371 A207372 * A207374 A207375 A207376

KEYWORD

nonn,base

AUTHOR

Carmine Suriano, Feb 17 2012

STATUS

approved

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Last modified February 16 14:47 EST 2019. Contains 320163 sequences. (Running on oeis4.)