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A074621
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a(n) = 6^n + 9^n.
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1
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2, 15, 117, 945, 7857, 66825, 578097, 5062905, 44726337, 397498185, 3547250577, 31743856665, 284606318817, 2554926522345, 22955156619057, 206361317079225, 1855841298759297, 16694108359111305, 150196195253667537
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listen;
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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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G.f.: 1/(1-6*x) + 1/(1-9*x).
E.g.f.: e^(6*x) + e^(9*x). (End)
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MATHEMATICA
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Table[6^n + 9^n, {n, 0, 20}]
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CROSSREFS
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Cf. A000051, A034472, A052539, A034474, A062394, A034491, A062395, A062396, A007689, A063376, A063481, A074600..A074624.
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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