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A131127
Table read by rows: 2*A007318(n,m) - A167374(n,m).
3
1, 3, 1, 2, 5, 1, 2, 6, 7, 1, 2, 8, 12, 9, 1, 2, 10, 20, 20, 11, 1, 2, 12, 30, 40, 30, 13, 1, 2, 14, 42, 70, 70, 42, 15, 1, 2, 16, 56, 112, 140, 112, 56, 17, 1, 2, 18, 72, 168, 252, 252, 168, 72, 19, 1, 2, 20, 90, 240, 420, 504, 420, 240, 90, 21, 1, 2, 22, 110, 330, 660, 924, 924, 660, 330, 110, 23, 1
OFFSET
0,2
COMMENTS
Row sums = A000079(n+1), n>0.
Warning: row sums are not A046055! - N. J. A. Sloane, Jul 08 2009
Row sums = A151821(n+1), n>=0. - Alois P. Heinz, Jul 13 2009
A167374 is a modified version of the pair operator A097806 with (1,1,1,...) in the main diagonal and (-1,-1,-1,...) in the subdiagonal.
LINKS
EXAMPLE
First few rows of the triangle:
1;
3, 1;
2, 5, 1;
2, 6, 7, 1;
2, 8, 12, 9, 1;
2, 10, 20, 20, 11, 1;
...
MAPLE
T:= (n, m)-> 2*binomial(n, m) -(-1)^(n+m)*`if`(n=m or n=m+1, 1, 0): seq(seq(T(n, m), m=0..n), n=0..12); # Alois P. Heinz, Jul 13 2009
MATHEMATICA
T[n_, m_] := 2*Binomial[n, m] - (-1)^(n+m)*If[n == m || n == m+1, 1, 0];
Table[Table[T[n, m], {m, 0, n}], {n, 0, 12}] // Flatten (* Jean-François Alcover, May 19 2016, translated from Maple *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jun 16 2007
EXTENSIONS
Edited by N. J. A. Sloane and R. J. Mathar, Jul 09 2009
Corrected and extended by Alois P. Heinz, Jul 13 2009
Definition simplified by Georg Fischer, Jun 07 2023
STATUS
approved