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%I #9 Aug 01 2019 01:12:54
%S 1015560,1446480,1854720,10155600,14464800,18547200,51665040,59552640,
%T 67944240,78127560,82623060,88560360,95236960,99497160,101556000,
%U 105094080,108656860,110937960,117681480,118072080,124942090,135647680
%N Numbers which can be expressed as the product of a number and its reversal in four different ways.
%H Chai Wah Wu, <a href="/A066598/b066598.txt">Table of n, a(n) for n = 1..10000</a>
%t f[n_] := (m = ToExpression[StringReverse[ToString[n]]]; If[n > m, n*m, 0]); a = Sort[ Table[ f[n], {n, 0, 10^6}]]; While[ a[[1]] == 0, a = Drop[a, 1]]; a[[ Select[ Range[ Length[a]] - 3, a[[ # ]] == a[[ # + 3 ]] & ]]]
%Y Cf. A066531.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Jan 08 2002
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