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5, 15, 45, 135, 405, 1215, 3645, 10935, 32805, 98415, 295245, 885735, 2657205, 7971615, 23914845, 71744535, 215233605, 645700815, 1937102445, 5811307335, 17433922005, 52301766015, 156905298045, 470715894135, 1412147682405, 4236443047215, 12709329141645
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,1
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LINKS
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FORMULA
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Limit_{n->oo} sigma(a(n))/a(n) = 9/5 = sigma(10)/10 (see Ward link). - Michel Marcus, Apr 30 2013
G.f.: 1/x + 2 - 2/x/G(0), where G(k)= 1 + 1/(1 - x*(5*k-3)/(x*(5*k+2) - 1/G(k+1))); (continued fraction). - Sergei N. Gladkovskii, Jun 04 2013
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MATHEMATICA
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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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