A207373 Numbers whose square is the product of a number and its reverse.

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

Offset: 1

Author

Carmine Suriano, Feb 17 2012

Keywords

• nonn
• base

Comments

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

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

Examples

			35143^2 = 96721*12769.
		

Links

• Giovanni Resta, Table of n, a(n) for n = 1..1169 (terms < 10^12, first 90 terms from Harvey P. Dale)

Crossrefs

Cf. A076750.

Programs

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 *)