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Search: id:A067689
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| A067689 |
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Inverse of determinant of n X n matrix whose (i,j)-th element is 1/(i+j). |
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+0
8
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| 2, 72, 43200, 423360000, 67212633600000, 172153600393420800000, 7097063852481244869427200000, 4702142622508202833251304734720000000, 50019370356486058711268515056654483456000000000
(list; graph; listen)
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OFFSET
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1,1
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REFERENCES
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Jerry Glynn and Theodore Gray, "The Beginner's Guide to Mathematica Version 4," Cambridge University Press, Cambridge UK, 2000, page 76.
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LINKS
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T. D. Noe, Table of n, a(n) for n=1..25
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FORMULA
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A067689 = A005249 * A000984 - Sharon Sela (sharonsela(AT)hotmail.com), Apr 18 2002.
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EXAMPLE
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The matrix begins:
1/2 1/3 1/4 1/5 1/6 1/7 1/8 ...
1/3 1/4 1/5 1/6 1/7 1/8 1/9 ...
1/4 1/5 1/6 1/7 1/8 1/9 1/10 ...
1/5 1/6 1/7 1/8 1/9 1/10 1/11 ...
1/6 1/7 1/8 1/9 1/10 1/11 1/12 ...
1/7 1/8 1/9 1/10 1/11 1/12 1/13 ...
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MATHEMATICA
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Table[ 1 / Det[ Table[ 1 / (i + j), {i, 1, n}, {j, 1, n} ]], {n, 1, 10} ]
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CROSSREFS
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Cf. A005249, A000984, A060739. See A005249 for a formula.
Sequence in context: A123072 A099681 A062082 this_sequence A079478 A036899 A041647
Adjacent sequences: A067686 A067687 A067688 this_sequence A067690 A067691 A067692
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KEYWORD
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nonn,nice
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AUTHOR
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Robert G. Wilson v (rgwv(AT)rgwv.com), Feb 04 2002
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