|
Search: id:A143996
|
|
|
| A143996 |
|
Rectangular array by antidiagonals: label each unit square in the 1st quadrant lattice by its northeast vertex (x,y) and mark squares for which (x,y) is congruent mod 4 to one of the following: (1,4), (2,2), (3,3), (4,1); then R(m,n) is the number of marked squares in the rectangle [0,m]x[0,n]. |
|
+0
6
|
|
| 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 2, 3, 3, 2, 1, 1, 3, 3, 4, 3, 3, 1, 2, 3, 4, 5, 5, 4, 3, 2, 2, 4, 5, 6, 6, 6, 5, 4, 2, 2, 4, 6, 7, 7, 7, 7, 6, 4, 2, 2, 5, 6, 8, 8, 9, 8, 8, 6, 5, 2, 3, 5, 7, 9, 10, 10, 10, 10, 9, 7, 5, 3, 3, 6, 8, 10, 11, 12, 12, 12, 11, 10, 8, 6, 3, 3, 6, 9, 11, 12, 13, 14
(list; table; graph; listen)
|
|
|
OFFSET
|
1,12
|
|
|
COMMENT
|
Row 4n is given by n*(1,2,3,4,5,6,...).
|
|
FORMULA
|
R(m,n)=Floor(mn/4).
|
|
CROSSREFS
|
Cf. A143997, A143998, A143999, A144000, A144001.
Sequence in context: A134143 A085684 A141604 this_sequence A071338 A078826 A051950
Adjacent sequences: A143993 A143994 A143995 this_sequence A143997 A143998 A143999
|
|
KEYWORD
|
nonn,tabl
|
|
AUTHOR
|
Clark Kimberling (ck6(AT)evansville.edu), Sep 07 2008
|
|
|
Search completed in 0.002 seconds
|
