|
Search: id:A123158
|
|
|
| A123158 |
|
Square array related to Bell nombers read by antidiagonals. |
|
+0
5
|
|
| 1, 1, 1, 2, 2, 1, 5, 5, 3, 1, 15, 15, 10, 5, 1, 52, 52, 37, 22, 6, 1, 203, 203, 151, 99, 31, 9, 1, 877, 877, 674, 471, 160, 61, 10, 1, 4140, 4140, 3263, 2386, 856, 385, 75, 14, 1, 21147, 21147, 17007, 12867, 4802, 2416, 520, 135, 15, 1
(list; table; graph; listen)
|
|
|
OFFSET
|
0,4
|
|
|
FORMULA
|
T(n,k)=0 if n<0, T(0,k)=1 for k>=0, T(n,k)=T(n,k-1)+1/2*(k+1)*T(n-1,k+1)if k is an odd number, T(n,k)=T(n,k-1)+T(n-1,k+1) if k is an even number . T(n,0)=A000110(n) ; T(n,1)=A000110(n+1) ; T(n,2)=A005493(n) ; T(n,3)=A033452(n) ; T(n,4)=A003128(n+2)
|
|
EXAMPLE
|
Square array begins:
1, 1, 1, 1, 1, ... (Row n=0 :A000012)
1, 2, 3, 5, 6, ... (Row n=1 :A117142)
2, 5, 10, 22, 31, ...
5, 15, 37, 99, 160, ...
15, 52, 151, 471, 856, ...
52, 203, 674, 2386, 4802, ...
|
|
CROSSREFS
|
Columns : A000110 (Bell numbers), A000110, A005493, A033452, A003128 ; Rows : A000012, A117142.
Adjacent sequences: A123155 A123156 A123157 this_sequence A123159 A123160 A123161
Sequence in context: A110488 A134379 A108087 this_sequence A133611 A010094 A019710
|
|
KEYWORD
|
easy,nonn,tabl
|
|
AUTHOR
|
Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Oct 01 2006
|
|
|
Search completed in 0.002 seconds
|
