OFFSET
1,1
COMMENTS
The integers in the LINKS illustration hang like ornaments on a tree.
LINKS
FORMULA
T(n,k)=1 if n even, 1<=k<=n.
T(n,k)=2 if n odd and (n+1)/2+k even, 1<=k<=n.
T(n,k)=0 if n odd and (n+1)/2+k odd, 1<=k<=n.
EXAMPLE
Triangle T(n,k) begins: Row sums
2; 2
1, 1; 2
0, 2, 0; 2
1, 1, 1, 1; 4
2, 0, 2, 0, 2; 6
1, 1, 1, 1, 1, 1; 6
0, 2, 0, 2, 0, 2, 0; 6
1, 1, 1, 1, 1, 1, 1, 1; 8
MAPLE
A257857 := proc(n, k)
if type(n, 'even') then
1 ;
elif type((n+1)/2+k, 'even') then
2 ;
else
0;
end if;
end proc:
CROSSREFS
KEYWORD
AUTHOR
Craig Knecht, Jul 12 2015
STATUS
approved