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%I #7 May 15 2017 10:59:08
%S 1,10,22,35,50,62,80,92,104,116,128,140,152,164,176,188,200,212,224,
%T 236,248,260,272,284,296,308,320,332,344,356,368,380,392,404,416,428,
%U 440,452,464,476,488,500,512,524,536,548,560,572,584,596,608,620
%N Number of ordered triples (w,x,y) with all terms in {-n,...,0,...,n} and w*x+w*y+x*y=w*x*y.
%C For a guide to related sequences, see A211422.
%F Conjectures from _Colin Barker_, May 15 2017: (Start)
%F G.f.: (1 + 8*x + 3*x^2 + x^3 + 2*x^4 - 3*x^5 + 6*x^6 - 6*x^7) / (1 - x)^2.
%F a(n) = 12*n + 8 for n>5.
%F a(n) = 2*a(n-1) - a(n-2) for n>7.
%F (End)
%t t[n_] := t[n] = Flatten[Table[w*x + w*y + x*y - w*x*y, {w, -n, n}, {x, -n, n}, {y, -n, n}]]
%t c[n_] := Count[t[n], 0]
%t t = Table[c[n], {n, 0, 80}] (* A211482 *)
%Y Cf. A211422.
%K nonn
%O 0,2
%A _Clark Kimberling_, Apr 12 2012
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