OFFSET
1,2
LINKS
Colin Barker, Table of n, a(n) for n = 1..100
FORMULA
Conjectures from Colin Barker, Feb 21 2015: (Start)
a(n) = -10*a(n-1)-25*a(n-2).
G.f. -x*(4*x-1) / (5*x+1)^2.
(End)
MATHEMATICA
f[i_, j_] := Max[3 i - 2 j, 3 j - 2 i];
m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}]
TableForm[m[8]] (* 8x8 principal submatrix *)
Flatten[Table[f[i, n + 1 - i],
{n, 1, 12}, {i, 1, n}]] (* A204158 *)
Table[Det[m[n]], {n, 1, 22}] (* A204240 *)
Permanent[m_] :=
With[{a = Array[x, Length[m]]},
Coefficient[Times @@ (m.a), Times @@ a]];
Table[Permanent[m[n]], {n, 1, 14}] (* A204241 *)
PROG
(PARI) vector(20, n, matdet(matrix(n, n, i, j, max(3*i-2*j, 3*j-2*i)))) \\ Colin Barker, Feb 21 2015
CROSSREFS
KEYWORD
sign
AUTHOR
Clark Kimberling, Jan 13 2012
STATUS
approved