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%I #10 Oct 17 2020 11:36:59
%S 0,1,1,1,3,3,3,3,6,8,8,8,8,8,8,8,10,10,12,12,12,12,12,12,14,16,16,21,
%T 21,21,21,21,25,25,25,25,27,27,27,27,29,29,29,29,29,29,29,29,31,33,35,
%U 35,35,35,39,39,41,41,41,41,41,41,41,41,48,48,48,48,48,48,48
%N Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^3=x*y.
%C For a guide to related sequences, see A211422.
%F a(n) = Sum_{i=1..n} Sum_{j=1..n} A010057(i*j). - _Ridouane Oudra_, Oct 17 2020
%t t[n_] := t[n] = Flatten[Table[w^3 - x*y, {w, 1, n}, {x, 1, n}, {y, 1, n}]]
%t c[n_] := Count[t[n], 0]
%t t = Table[c[n], {n, 0, 70}] (* A211515 *)
%Y Cf. A211422, A010057.
%K nonn
%O 0,5
%A _Clark Kimberling_, Apr 14 2012
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