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A103458
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a(n) = 7^n + 1 - 0^n.
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2
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1, 8, 50, 344, 2402, 16808, 117650, 823544, 5764802, 40353608, 282475250, 1977326744, 13841287202, 96889010408, 678223072850, 4747561509944, 33232930569602, 232630513987208, 1628413597910450, 11398895185373144
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OFFSET
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0,2
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COMMENTS
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a(n)^3 is palindromic in base 7 (1_7, 1331_7, 1030301_7, 1003003001_7, ...).
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LINKS
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FORMULA
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G.f.: (1-7*x^2)/((1-x)*(1-7*x)).
a(n) = Sum_{k=0..n} binomial(n, k)*0^(k(n-k))*7^k.
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MATHEMATICA
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Table[7^n +1 -Boole[n==0], {n, 0, 30}] (* G. C. Greubel, Jun 22 2021 *)
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PROG
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(Magma) [1] cat [7^n + 1: n in [1..30]]; // G. C. Greubel, Jun 22 2021
(Sage) [1]+[7^n + 1 for n in (1..30)] # G. C. Greubel, Jun 22 2021
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CROSSREFS
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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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