|
|
A212056
|
|
Number of (w,x,y,z) with all terms in {1,...,n} and w*x>y*z+2.
|
|
3
|
|
|
0, 0, 1, 19, 80, 230, 521, 1019, 1800, 2966, 4593, 6819, 9768, 13566, 18353, 24339, 31640, 40478, 51025, 63523, 78168, 95230, 114881, 137459, 163184, 192374, 225265, 262251, 303568, 349606, 400633, 457099, 519280, 587654, 662481
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,4
|
|
COMMENTS
|
|
|
LINKS
|
|
|
MATHEMATICA
|
t = Compile[{{n, _Integer}}, Module[{s = 0},
(Do[If[w*x > y*z + 2, s = s + 1],
{w, 1, #}, {x, 1, #}, {y, 1, #}, {z, 1, #}] &[n]; s)]];
Map[t[#] &, Range[0, 50]] (* A212056 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|