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A211437
Number of ordered triples (w,x,y) with all terms in {-n,...,0,...,n} and w*x*y=n.
2
1, 4, 12, 12, 24, 12, 36, 12, 40, 24, 36, 12, 72, 12, 36, 36, 60, 12, 72, 12, 72, 36, 36, 12, 120, 24, 36, 40, 72, 12, 108, 12, 84, 36, 36, 36, 144, 12, 36, 36, 120, 12, 108, 12, 72, 72, 36, 12, 180, 24, 72, 36, 72, 12, 120, 36, 120, 36, 36, 12, 216, 12, 36, 72
OFFSET
0,2
COMMENTS
For a guide to related sequences, see A211422.
MATHEMATICA
t[n_] := t[n] = Flatten[Table[w*x*y - n, {w, -n, n}, {x, -n, n}, {y, -n, n}]]
c[n_] := Count[t[n], 0]
t = Table[c[n], {n, 0, 80}] (* A211437 *)
t/4 (* A007425 for n>0 *)
CROSSREFS
Sequence in context: A120213 A005886 A096442 * A195199 A294628 A323188
KEYWORD
nonn
AUTHOR
Clark Kimberling, Apr 12 2012
STATUS
approved