|
|
|
|
0, 0, 0, 0, 0, 1, 1, 5, 6, 10, 11, 19, 20, 29, 33, 38, 43, 56, 60, 76, 81, 90, 98, 118, 121, 138, 147, 163, 172, 197, 202, 230, 243, 260, 273, 294, 303, 336, 352, 373, 384, 421, 430, 470, 487, 508, 528, 572, 583, 623, 640
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,8
|
|
LINKS
|
|
|
PROG
|
(Python)
def t(n):
s=0
for a in range(0, n+1):
for b in range(0, n+1):
for c in range(0, n+1):
for d in range(0, n+1):
if (a!=b and a!=d and b!=d and c!=a and c!=b and c!=d):
if abs(a*d-b*c)==1:
s+=1
return s
for i in range(0, 201):
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|