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A074608
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a(n) = 3^n + 7^n.
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7
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2, 10, 58, 370, 2482, 17050, 118378, 825730, 5771362, 40373290, 282534298, 1977503890, 13841818642, 96890604730, 678227855818, 4747575858850, 33232973616322, 232630643127370, 1628413985330938, 11398896347634610
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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/(1-3*x) + 1/(1-7*x).
E.g.f.: exp(3*x) + exp(7*x). (End)
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MATHEMATICA
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Table[3^n + 7^n, {n, 0, 25}]
RecurrenceTable[{a[0]== 2, a[1]== 10, a[n]== 10*a[n-1] - 21*a[n-2]}, a, {n, 30}] (* G. C. Greubel, Aug 20 2015 *)
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PROG
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(PARI) Vec(1/(1-3*x) + 1/(1-7*x) + O(x^50)) \\ Altug Alkan, Oct 12 2015
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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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