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A084999 Determinant of a certain n X n matrix whose elements are the integers 1 to n^2. 0
1, -10, 260, -9002, 391860, -20256038, 1211950740, -82281893850, 6247844526420, -524546069736150, 48243794823724500, -4823577417987578250, 520903033165862392500, -60422912433611865159750, 7492466897219978346172500 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Fill the main diagonal, then come back up the adjacent diagonal, skip over to the other adjacent diagonal and precede with 2n through 3n-2, etc.

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Matrix of order 4 is:

1 8 13 16

7 2 9 14

12 6 3 10

15 11 5 4

PROG

(PARI) {init_m(n)= m=matrix(n, n, row, col, row*(row==col)); next_entry=n+1; for(i=2, n, col=n-i+1; forstep(row=n, i, -1, m[row, col]=next_entry; next_entry++; col--); col=i; for(row=1, n-i+1, m[row, col]=next_entry; next_entry++; col++))} for(n=1, 15, init_m(n); print1(matdet(m), ", ")) (Rick L. Shepherd)

CROSSREFS

Sequence in context: A001824 A024294 A183406 * A268730 A217911 A054593

Adjacent sequences:  A084996 A084997 A084998 * A085000 A085001 A085002

KEYWORD

sign

AUTHOR

Robert G. Wilson v, Jun 16 2003

EXTENSIONS

Corrected by Rick L. Shepherd, Jun 12 2004

STATUS

approved

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Last modified September 29 12:15 EDT 2020. Contains 337431 sequences. (Running on oeis4.)