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A255266 Numbers representable in more than one way as x*y*(x+y), where x>=y>1.

%I A255266 #14 May 10 2021 07:39:21
%S A255266 240,390,810,880,1008,1020,1680,1920,2100,2310,2970,3120,3360,3696,
%T A255266 3750,4320,4914,5460,5670,6090,6270,6480,6630,7040,7380,7440,7770,
%U A255266 8064,8160,8190,8448,8580,8976,9240,9520,10290,10530,10640,11340,11856,12474,13440,13776,14040
%N A255266 Numbers representable in more than one way as x*y*(x+y), where x>=y>1.
%e A255266 a(3) = 810 = 15*3*(15+3) = 9*6*(9+6).
%o A255266 (Python)
%o A255266 TOP = 100000
%o A255266 a = [0]*TOP
%o A255266 for y in range(2, TOP//2):
%o A255266   for x in range(y, TOP//2):
%o A255266     k = x*y*(x+y)
%o A255266     if k>=TOP: break
%o A255266     a[k]+=1
%o A255266 print([n for n in range(TOP) if a[n]>1])
%Y A255266 Cf. A255265, A081779.
%K A255266 nonn
%O A255266 1,1
%A A255266 _Alex Ratushnyak_, Feb 19 2015