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A088021 (n^2)!/(n!)^2. +0
4
1, 1, 6, 10080, 36324288000, 1077167364120207360000, 717579719887926731226850787328000000, 23946596436219275985459662514223331478629410406400000000 (list; graph; listen)
OFFSET

0,3

COMMENT

Based on an observation of Hugo Pfoertner, Edwin Clark conjectured and Xiang-dong Hou proved that (n^2)!/(n!)^2 gives the number of distinct determinants of the generic n X n matrix whose entries are n^2 different indeterminates under all (n^2)! permutations of the entries.

Using J. T. Schwarz' Sparse Zeros Lemma this implies that for any positive integer n there is an n X n matrix A with positive integer entries such that the set of determinant values obtained from A by permuting the elements of A is (n^2)!/(n!)^2.

Moreover, for any entries, no larger number of determinants can be obtained. In fact, by the Sparse Zeros Lemma one can select the entries of A from any sufficiently large subset of real numbers.

FORMULA

a(n)=A088020(n)/A001044(n).

CROSSREFS

Cf. A001044, A088020.

Sequence in context: A061109 A013784 A137040 this_sequence A069942 A093897 A062782

Adjacent sequences: A088018 A088019 A088020 this_sequence A088022 A088023 A088024

KEYWORD

nonn

AUTHOR

Hugo Pfoertner (hugo(AT)pfoertner.org), Sep 18 2003

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Last modified September 4 21:24 EDT 2008. Contains 143414 sequences.


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