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A225817
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Moebius function applied to divisors of n, table read by rows.
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9
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1, 1, -1, 1, -1, 1, -1, 0, 1, -1, 1, -1, -1, 1, 1, -1, 1, -1, 0, 0, 1, -1, 0, 1, -1, -1, 1, 1, -1, 1, -1, -1, 0, 1, 0, 1, -1, 1, -1, -1, 1, 1, -1, -1, 1, 1, -1, 0, 0, 0, 1, -1, 1, -1, -1, 1, 0, 0, 1, -1, 1, -1, 0, -1, 1, 0, 1, -1, -1, 1, 1, -1, -1, 1, 1, -1
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OFFSET
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1
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COMMENTS
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T(n,1) = 1; for n > 1: T(n,2) = -1;
A048105(n) = number of zeros in row n;
A034444(n) = number of nonzero terms in row n;
A007875(n) = number of ones in row n.
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LINKS
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EXAMPLE
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. -----+-----------------------------------+-- divisors of n: -----------
. 1 | 1 | 1
. 2 | 1 -1 | 1,2
. 3 | 1 -1 | 1,3
. 4 | 1 -1 0 | 1,2,4
. 5 | 1 -1 | 1,5
. 6 | 1 -1 -1 1 | 1,2,3,6
. 7 | 1 -1 | 1,7
. 8 | 1 -1 0 0 | 1,2,4,8
. 9 | 1 -1 0 | 1,3,9
. 10 | 1 -1 -1 1 | 1,2,5,10
. 11 | 1 -1 | 1,11
. 12 | 1 -1 -1 0 1 0 | 1,2,3,4,6,12
. 13 | 1 -1 | 1,13
. 14 | 1 -1 -1 1 | 1,2,7,14
. 15 | 1 -1 -1 1 | 1,3,5,15
. 16 | 1 -1 0 0 0 | 1,2,4,8,16
. 17 | 1 -1 | 1,17
. 18 | 1 -1 -1 1 0 0 | 1,2,3,6,9,18
. 19 | 1 -1 | 1,19
. 20 | 1 -1 0 -1 1 0 | 1,2,4,5,10,20
. 21 | 1 -1 -1 1 | 1,3,7,21
. 22 | 1 -1 -1 1 | 1,2,11,22
. 23 | 1 -1 | 1,23
. 24 | 1 -1 -1 0 1 0 0 0 | 1,2,3,4,6,8,12,24
. 25 | 1 -1 0 | 1,5,25
. 26 | 1 -1 -1 1 | 1,2,13,26
. 27 | 1 -1 0 0 | 1,3,9,27
. 28 | 1 -1 0 -1 1 0 | 1,2,4,7,14,28
. 29 | 1 -1 | 1,29
. 30 | 1 -1 -1 -1 1 1 1 -1 | 1,2,3,5,6,10,15,30 .
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MATHEMATICA
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Table[Map[MoebiusMu, Divisors[n]], {n, 1, 20}] // Grid (* Geoffrey Critzer, Dec 10 2014 *)
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PROG
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(Haskell)
a225817 n k = a225817_tabf !! (n-1) !! (k-1)
a225817_row n = a225817_tabf !! (n-1)
a225817_tabf = map (map a008683) a027750_tabf
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CROSSREFS
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KEYWORD
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sign,tabf
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AUTHOR
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STATUS
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approved
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