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A181044
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The number of ways to compute the determinant of an n X n matrix using cofactor expansion.
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2
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OFFSET
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1,2
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REFERENCES
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Robert A. Beeler, How to Count: An Introduction to Combinatorics and Its Applications, Springer International Publishing, 2015. See Theorem 6.1.9 at p. 153.
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LINKS
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FORMULA
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a(n) = 2*n*(a(n-1))^n.
a(n) = 2*2^n*2^(n*(n-1))*2^(n*(n-1)*(n-2))*...*2^(n*(n-1)*...*4*3)*n*(n-1)^n*(n-2)^(n*(n-1))*(n-3)^(n*(n-1)*(n-2))*...*2^(n*(n-1)*...*4*3).
4^(n!*(e-2)) < a(n) < (2*e)^(n!*(e-2)).
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MATHEMATICA
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a[1]=1; a[n_]:=2n a[n-1]^n; Array[a, 5] (* Stefano Spezia, Jun 20 2023 *)
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PROG
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(PARI) a(n) = if (n==1, 1, 2*n*a(n-1)^n); \\ Michel Marcus, Jun 21 2023
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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