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Even squares which can be expressed as the product of a number and its reversal in at least two different ways.
5

%I #31 Aug 01 2019 01:07:32

%S 63504,435600,6350400,7683984,16240900,25401600,43560000,66585600,

%T 420332004,558471424,635040000,647804304,726949444,768398400,

%U 782432784,1067328900,1624090000,1897473600,2341011456,2540160000

%N Even squares which can be expressed as the product of a number and its reversal in at least two different ways.

%C For n=1..49 identical to A083408.

%D S. S. Gupta, EPRNs, Science Today, Feb. 1987, India.

%H Chai Wah Wu, <a href="/A083406/b083406.txt">Table of n, a(n) for n = 1..2372</a> (first 73 terms from Hans Havermann)

%H Shyam Sunder Gupta, <a href="http://www.shyamsundergupta.com/eporns.htm">Equal Product of Reversible Numbers</a>

%e 63504 = 252 * 252 = 144 * 441, 7683984 = 2772 * 2772 = 1584 * 4851, etc.

%Y Cf. A031877, A066531, A083407 (odd squares version), A083408 (all squares version).

%K nonn,base

%O 1,1

%A _Shyam Sunder Gupta_, Jun 07 2003

%E Corrected and extended by _Hans Havermann_, Feb 11 2012

%E Definition corrected by _N. J. A. Sloane_, Aug 01 2019