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A133577
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a(n)=a(n-1)+10*a(n-2) for n>=2, a(0)=1, a(1)=2 .
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2
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1, 2, 12, 32, 152, 472, 1992, 6712, 26632, 93752, 360072, 1297592, 4898312, 17874232, 66857352, 245599672, 914173192, 3370169912, 12511901832, 46213600952, 171332619272, 633468628792, 2346794821512, 8681481109432
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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FORMULA
| G.f.: (1+x)/(1-x-10*x^2) .
a(n)=Sum_{k, 0<=k<=n+1}A122950(n+1,k)*9^(n+1-k). - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jan 08 2008
a(n)=(1/2)*[(1/2)-(1/2)*sqrt(41)]^n+(3/82)*sqrt(41)*[(1/2)+(1/2)*sqrt(41)]^n-(3/82)*sqrt(41)*[(1/2)-(1 /2)*sqrt(41)]^n+(1/2)*[(1/2)+(1/2)*sqrt(41)]^n, with n>=0 [From Paolo P. Lava (paoloplava(AT)gmail.com), Nov 18 2008]
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CROSSREFS
| Sequence in context: A092345 A102080 A000647 * A106185 A098203 A055707
Adjacent sequences: A133574 A133575 A133576 * A133578 A133579 A133580
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KEYWORD
| easy,nonn
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AUTHOR
| Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jan 03 2008
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