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

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