OFFSET
0,4
COMMENTS
Unsigned row sums appear to be A014739.
EXAMPLE
Start with a signed version of A061554:
1;
1, 1;
-2, 1, 1;
-3, -3, 1, 1;
6, -4, -4, 1, 1;
10, 10, -5, -5, 1;
...
and invert it, getting:
1
-1, 1;
3, -1, 1;
-3, 4, -1, 1;
5, -4, 5, -1, 1;
-5, 9, -5, 6, -1, 1;
...
MAPLE
A061554 := proc(n, k) binomial(n+k, floor(k/2)) ; end: nmax := 13 : A := array(1..nmax, 1..nmax) : for r from 1 to nmax do for c from 1 to nmax do A[r, c] := A061554(c-1, r-c)*(-1)^floor((r-c)/2) ; od: od: A := linalg[inverse](A) : for r from 1 to nmax do for c from 1 to r do printf("%d, ", A[r, c]) ; od: od: # R. J. Mathar, Jan 31 2008
MATHEMATICA
A061554[n_, k_] := Binomial[n+k, Floor[k/2]];
nmax = 13;
A = Table[A061554[c-1, r-c]*(-1)^Floor[(r-c)/2], {r, nmax}, {c, nmax}];
A = Inverse[A];
Table[A[[r, c]], {r, nmax}, {c, r}] // Flatten (* Jean-François Alcover, May 01 2023 *)
CROSSREFS
KEYWORD
AUTHOR
Gary W. Adamson, Nov 27 2006
EXTENSIONS
Edited by N. J. A. Sloane, Dec 01 2006
More terms from R. J. Mathar, Jan 31 2008
STATUS
approved