|
|
A143901
|
|
Rectangular array R by antidiagonals: R(m,n) = floor((m*n+1)/2).
|
|
1
|
|
|
1, 1, 1, 2, 2, 2, 2, 3, 3, 2, 3, 4, 5, 4, 3, 3, 5, 6, 6, 5, 3, 4, 6, 8, 8, 8, 6, 4, 4, 7, 9, 10, 10, 9, 7, 4, 5, 8, 11, 12, 13, 12, 11, 8, 5, 5, 9, 12, 14, 15, 15, 14, 12, 9, 5, 6, 10, 14, 16, 18, 18, 18, 16, 14, 10, 6, 6, 11, 15, 18, 20, 21, 21, 20, 18, 15, 11, 6, 7, 12, 17, 20, 23, 24, 25, 24
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,4
|
|
COMMENTS
|
Old name was: R(m,n) = number of white squares.
|
|
LINKS
|
|
|
EXAMPLE
|
Northwest corner:
1 1 2 2 3 3 4 4
1 2 3 4 5 6 7 8
2 3 5 6 8 9 11 12
2 4 6 8 10 12 14 16
|
|
CROSSREFS
|
Antidiagonal sums: (1,2,6,10,19,...)=A005993.
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|