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A165323
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a(0)=1, a(1)=8, a(n)=17*a(n-1)-64*a(n-2) for n>1.
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2
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1, 8, 72, 712, 7496, 81864, 911944, 10263752, 116119368, 1317149128, 14959895624, 170020681416, 1932918264136, 21978286879688, 249924108049992, 2842099476549832, 32320548186147656, 367554952665320904
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(n)/a(n-1) tends to (17+sqrt(33))/2 = 11.3722813...
For n>=2, a(n) equals 8^n times the permanent of the (2n-2)X(2n-2) tridiagonal matrix with 1/sqrt(8)'s along the main diagonal, and 1's along the superdiagonal and the subdiagonal. [From John M. Campbell, Jul 08 2011]
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FORMULA
| G.f.: (1-9x)/(1-17x+64x^2). a(n)= Sum_{k, 0<=k<=n}A165253(n,k)*8^(n-k).
a(n) = ((33-sqrt(33))*(17+sqrt(33))^n+(33+sqrt(33))*(17-sqrt(33))^n)/(66*2^n). [From Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Sep 28 2009]
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CROSSREFS
| Sequence in context: A082414 A145303 A098411 * A082366 A049388 A014479
Adjacent sequences: A165320 A165321 A165322 * A165324 A165325 A165326
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KEYWORD
| nonn
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AUTHOR
| Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 14 2009
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