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Search: id:A155144
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| A155144 |
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a(n)=9*a(n-1)+9*a(n-2), n>2 ; a(0)=1, a(1)=8, a(2)=80 . |
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+0
1
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| 1, 8, 80, 792, 7848, 77760, 770472, 7634088, 75641040, 749476152, 7426054728, 73579777920, 729052493832, 7223690445768, 71574686456400, 709185392119512, 7026840707183208, 69624234893724480, 689859680408169192
(list; graph; listen)
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OFFSET
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0,2
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FORMULA
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G.f.: (1-x-x^2)/(1-9*x-9*x^2).
a(n)=4*{[(9/2)+(3/2)*sqrt(13)]^(n-1)+[(9/2)-(3/2)*sqrt(13)]^(n-1)}+(44/39)*sqrt(13)*{[(9/2)+(3/2)*sqrt(13)]^(n-1)-[(9/2)-(3/2)*sqrt(13)]^(n-1)}+(1/9)*[C(2*n,n) mod 2], with n>=0 [From Paolo P. Lava (ppl(AT)spl.at), Jan 26 2009]
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CROSSREFS
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Sequence in context: A166157 A145729 A024101 this_sequence A136949 A102592 A053175
Adjacent sequences: A155141 A155142 A155143 this_sequence A155145 A155146 A155147
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KEYWORD
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nonn
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AUTHOR
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Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jan 21 2009
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