|
|
A212244
|
|
Number of (w,x,y,z) with all terms in {1,...,n} and w + n = x*y*z.
|
|
2
|
|
|
0, 0, 3, 9, 13, 22, 31, 37, 48, 60, 69, 81, 93, 102, 118, 136, 142, 154, 178, 184, 202, 220, 229, 250, 265, 280, 295, 315, 333, 345, 372, 378, 400, 424, 433, 457, 481, 487, 511, 535, 550, 568, 595, 607, 625, 661, 676, 688, 712, 724, 757, 775, 787, 817
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
COMMENTS
|
For a guide to related sequences, see A211795.
|
|
LINKS
|
|
|
MATHEMATICA
|
t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[w == x*y*z - n, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 60]] (* A212244 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|