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A211512 Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2=3x*y. 2
0, 0, 0, 2, 2, 2, 6, 6, 6, 8, 8, 8, 14, 14, 14, 16, 18, 18, 22, 22, 22, 24, 24, 24, 30, 32, 32, 38, 38, 38, 44, 44, 46, 48, 48, 48, 56, 56, 56, 58, 58, 58, 62, 62, 62, 66, 66, 66, 76, 80, 82, 84, 84, 84, 92, 92, 92, 94, 94, 94, 104, 104, 104, 108, 112, 112, 116 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

For a guide to related sequences, see A211422.

LINKS

Table of n, a(n) for n=0..66.

MATHEMATICA

t[n_] := t[n] = Flatten[Table[w^2 - 3 x*y, {w, 1, n}, {x, 1, n}, {y, 1, n}]]

c[n_] := Count[t[n], 0]

t = Table[c[n], {n, 0, 70}]  (* A211512 *)

t/2                          (* integers *)

CROSSREFS

Cf. A211422.

Sequence in context: A214078 A155453 A032558 * A139552 A292140 A064943

Adjacent sequences:  A211509 A211510 A211511 * A211513 A211514 A211515

KEYWORD

nonn

AUTHOR

Clark Kimberling, Apr 14 2012

STATUS

approved

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Last modified September 21 19:57 EDT 2019. Contains 327281 sequences. (Running on oeis4.)