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 A086815 a(n)=(n-1)*n^(2*n) 1

%I #7 Jul 23 2013 18:13:07

%S 0,16,1458,196608,39062500,10883911680,4069338437094,1970324836974592,

%T 1200757082375992968,900000000000000000000,814027493868397611133210,

%U 874465319237299285467856896,1100799962319223399900795392108

%N a(n)=(n-1)*n^(2*n)

%C (-1)*determinant of the 2n X 2n matrix M_(i,j)=j if (i+j) is multiple of n, M_(i,j)=i otherwise.

%e For n=3 the matrix is : [1 2 1 1 5 1], [1 2 2 4 2 2], [3 3 3 3 3 6], [4 2 4 4 5 4], [1 5 5 4 5 5], [6 6 3 6 6 6]

%t Table[(n-1)n^(2n),{n,20}] (* _Harvey P. Dale_, Jul 23 2013 *)

%o (PARI) a(n)=(n-1)*n^(2*n)

%Y Cf. A062206.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Aug 06 2003

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Last modified July 22 00:08 EDT 2024. Contains 374478 sequences. (Running on oeis4.)