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Search: id:A016209
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| A016209 |
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Expansion of 1/((1-x)(1-3x)(1-5x)). |
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+0
3
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| 1, 9, 58, 330, 1771, 9219, 47188, 239220, 1205941, 6059229, 30384718, 152189310, 761743711, 3811110039, 19062724648, 95335146600, 476740303081, 2383895225649, 11920057258978, 59602029687090
(list; graph; listen)
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OFFSET
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0,2
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COMMENT
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T(n+2,2) where T=A039755.
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FORMULA
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a(n) =(5^(n+2)-2*3^(n+2)+1)/8 =a(n-1)+A005059(n+1) =8*a(n-1)-15*a(n-2)+2 =(A003463(n+2)-A003462(n+2))/2 - Henry Bottomley (se16(AT)btinternet.com), Jun 06 2000
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MAPLE
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a:=n->sum((5^(n-j)-3^(n-j))/2, j=0..n): seq(a(n), n=1..20); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jan 04 2007
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PROGRAM
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(PARI) a(n)=if(n<0, 0, n+=2; (5^n-2*3^n+1)/8)
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CROSSREFS
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Cf. A016218, A016208, A000392, A000225, A003462, A003463, A003464, A023000, A023001, A002452, A002275, A016123, A016125, A016256.
Sequence in context: A026750 A009034 A026377 this_sequence A129173 A055423 A027249
Adjacent sequences: A016206 A016207 A016208 this_sequence A016210 A016211 A016212
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane (njas(AT)research.att.com).
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