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A083068
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7th row of number array A083064.
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7
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1, 7, 55, 439, 3511, 28087, 224695, 1797559, 14380471, 115043767, 920350135, 7362801079, 58902408631, 471219269047, 3769754152375, 30158033218999, 241264265751991, 1930114126015927, 15440913008127415, 123527304065019319, 988218432520154551, 7905747460161236407
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OFFSET
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0,2
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COMMENTS
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Let A be the Hessenberg matrix of order n, defined by: A[1,j]=1, A[i,i]:=10, (i>1), A[i,i-1]=-1, and A[i,j]=0 otherwise. Then, for n>=1, a(n-1)=(-1)^(n-1)*charpoly(A,2). - Milan Janjic, Feb 21 2010
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LINKS
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FORMULA
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a(n) = (6*8^n+1)/7.
G.f. (1-2*x)/((1-8*x)(1-x)).
E.g.f. (6*exp(8*x)+exp(x))/7.
a(n) = 8^n - sum(8^i, i=0..n-1) for n>0. - Bruno Berselli, Jun 20 2013
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MATHEMATICA
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LinearRecurrence[{9, -8}, {1, 7}, 20] (* Harvey P. Dale, Jul 18 2019 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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