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A118712 a(n) = Determinant of n X n circulant matrix whose first row is A000001(1), A000001(2), ..., A000001(n) where A000001(n) = number of groups of order n. 1

%I #7 Nov 17 2013 20:20:21

%S 1,0,0,-5,6,-16,9,-134400,647248,-1711908,6076067,-85248000,116477425,

%T -1764364437,909276004,-522319050599375232,14313181351994538493,

%U -165893335414907083200,2939566160282258664451,-5007637771411479278976,75399747694572065660672

%N a(n) = Determinant of n X n circulant matrix whose first row is A000001(1), A000001(2), ..., A000001(n) where A000001(n) = number of groups of order n.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CirculantMatrix.html">Circulant Matrix</a>.

%e a(4) = -5 because of the determinant -5 =

%e |1,1,1,2|

%e |2,1,1,1|

%e |1,2,1,1|

%e |1,1,2,1|.

%e a(11) = 6076067 = determinant

%e |1, 1, 1, 2, 1, 2, 1, 5, 2, 2, 1|

%e |1, 1, 1, 1, 2, 1, 2, 1, 5, 2, 2|

%e |2, 1, 1, 1, 1, 2, 1, 2, 1, 5, 2|

%e |2, 2, 1, 1, 1, 1, 2, 1, 2, 1, 5|

%e |5, 2, 2, 1, 1, 1, 1, 2, 1, 2, 1|

%e |1, 5, 2, 2, 1, 1, 1, 1, 2, 1, 2|

%e |2, 1, 5, 2, 2, 1, 1, 1, 1, 2, 1|

%e |1, 2, 1, 5, 2, 2, 1, 1, 1, 1, 2|

%e |2, 1, 2, 1, 5, 2, 2, 1, 1, 1, 1|

%e |1, 2, 1, 2, 1, 5, 2, 2, 1, 1, 1|

%e |1, 1, 2, 1, 2, 1, 5, 2, 2, 1, 1|.

%o (GAP) A118712 := n -> DeterminantMat(List([0..n-1], i->List([0..n-1], j->NrSmallGroups(((j-i) mod n)+1)))); # _Eric M. Schmidt_, Nov 17 2013

%Y Cf. A000001, A048954, A052182, A066933, A086459, A086569.

%K sign

%O 1,4

%A _Jonathan Vos Post_, May 20 2006

%E a(1) corrected by and more terms from _Eric M. Schmidt_, Nov 17 2013

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Last modified April 19 03:46 EDT 2024. Contains 371782 sequences. (Running on oeis4.)