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A071084 Determinant of the n X n matrix whose element (i,j) equals t(|i-j|) where t(n) is the number of divisors of n and t(0) = 0. 2
0, -1, 4, -7, 10, 68, -578, 3825, -14508, 38367, -46170, 37125, 740520, 7341147, -211529660, 2662060613, -31141230062, 234276517760, -1130151516242, 4893200552669, -6576135166508 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..21.

MATHEMATICA

f[n_] := Det[ Table[ If[i == j, 0, DivisorSigma[0, Abs[i - j]]], {i, 1, n}, {j, 1, n}]]; Table[Abs[f[n]], {n, 1, 21}]

CROSSREFS

Sequence in context: A100591 A135262 A061515 * A175833 A171964 A198468

Adjacent sequences:  A071081 A071082 A071083 * A071085 A071086 A071087

KEYWORD

sign

AUTHOR

Robert G. Wilson v, May 26 2002

STATUS

approved

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Last modified April 24 12:32 EDT 2014. Contains 240983 sequences.