%I #4 Apr 15 2012 21:22:09
%S 1,5,9,21,33,37,49,53,65,77,81,85,113,117,121,133,153,157,169,173,185,
%T 197,201,205,233,253,257,301,313,317,329,333,353,365,369,373,401,405,
%U 409,421,433,437,449,453,465,477,481,485,537,573,593,605,617
%N Number of ordered triples (w,x,y) with all terms in {-n,...,0,...,n} and 3*w^2+x*y=0.
%C For a guide to related sequences, see A211422.
%t t[n_] := t[n] = Flatten[Table[3 w^2 + 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, 90}] (* A211427 *)
%t (t - 1)/4 (* integers *)
%Y Cf. A211422.
%K nonn
%O 0,2
%A _Clark Kimberling_, Apr 10 2012
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