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A351154
a(n) is the permanent of the n X n matrix M(n) that is defined as M[i,j,n] = A351153(n, min(i, j)) + abs(i - j).
1
1, 1, 7, 169, 10388, 1324344, 305668180, 116145817656, 67770421715800, 57594670663866124, 68393751368082128320, 109765035421144948709232, 231657098706747226470685920, 628412716450312334529486247152, 2149132484027947970192241804640128, 9113755489596517688997731211571700256
OFFSET
0,3
COMMENTS
Conjectures: (Start)
det(M(0)) = det(M(1)) = 1 and det(M(n)) = -(n - 2)! for n > 1.
abs(det(M(n))) = abs(A159333(n-2)). (End)
EXAMPLE
a(3) = 169:
1 2 3
2 4 5
3 5 6
a(4) = 10388:
1 2 3 4
2 5 6 7
3 6 8 9
4 7 9 10
MATHEMATICA
A351153[n_, k_]:=n(k-1)-k(k-3)/2; M[i_, j_, n_]:=A351153[n, Min[i, j]]+Abs[i-j]; a[n_]:=Permanent[Table[M[i, j, n], {i, n}, {j, n}]]; Join[{1}, Array[a, 15]]
PROG
(PARI) t(n, k) = n*(k-1) - k*(k-3)/2; \\ A351153
a(n) = matpermanent(matrix(n, n, i, j, t(n, min(i, j)) + abs(i - j))); \\ Michel Marcus, Feb 03 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Stefano Spezia, Feb 02 2022
STATUS
approved