OFFSET
1,2
LINKS
David Singmaster, David Fielker, N. J. A. Sloane, Correspondence, August 1979
EXAMPLE
Northwest corner:
1...3...5....7....9
3...6...9....12...15
5...9...13...17...21
7...12..17...22...27
MATHEMATICA
f[i_, j_] := i*j + i + j - 2;
m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
TableForm[m[5]] (* 5x5 principal submatrix *)
Flatten[Table[f[i, n + 1 - i],
{n, 1, 12}, {i, 1, n}]] (* A204250 *)
Permanent[m_] :=
With[{a = Array[x, Length[m]]},
Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 14}] (* A204251 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Jan 14 2012
STATUS
approved