login
Square array T read by antidiagonals: T(n,k) = 0 if n-k>=4 or if k-n>=4, T(3,0) = T(2,0) = TT(1,0) = T(0,0) = T(0,1) = T(0,2) = T(0,3) = 1, T(n,k) = T(n-1,k) + T(n,k-1).
12

%I #7 Mar 13 2013 13:30:44

%S 1,1,1,1,2,1,1,3,3,1,0,4,6,4,0,0,4,10,10,4,0,0,0,14,20,14,0,0,0,0,14,

%T 34,34,14,0,0,0,0,0,48,68,48,0,0,0,0,0,0,48,116,116,48,0,0,0,0,0,0,0,

%U 164,232,164,0,0,0,0

%N Square array T read by antidiagonals: T(n,k) = 0 if n-k>=4 or if k-n>=4, T(3,0) = T(2,0) = TT(1,0) = T(0,0) = T(0,1) = T(0,2) = T(0,3) = 1, T(n,k) = T(n-1,k) + T(n,k-1).

%F T(n,n) = A006012(n).

%F T(n,n+1) = T(n+1,n) = A007052(n).

%F T(n,n+2) = T(n,n+3) = T(n+2,n) = T(n+3,n) = A007070(n).

%F Sum_{k, 0<=k<=n} T(n-k,k) = A068912(n).

%e Square array begins:

%e 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, ... row n=0

%e 1, 2, 3, 4, 4, 0, 0, 0, 0, 0, ... row n=1

%e 1, 3, 6, 10, 14, 14, 0, 0, 0, 0, ... row n=2

%e 1, 4, 10, 20, 34, 48, 48, 0, 0, 0, ... row n=3

%e 0, 4, 14, 34, 68, 116, 164, 164, 0, 0, ... row n=4

%e 0, 0, 14, 48, 116, 232, 396, 560, 560, 0, ... row n=5

%e 0, 0, 0, 48, 164, 396, 792, 1352, 1912, 1912, row n=6

%e ...

%Y Cf. A006012, A007052, A007070, A068912

%K nonn,tabl

%O 0,5

%A _Philippe Deléham_, Mar 12 2013