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A218722
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a(n) = (19^n-1)/18.
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40
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0, 1, 20, 381, 7240, 137561, 2613660, 49659541, 943531280, 17927094321, 340614792100, 6471681049901, 122961939948120, 2336276859014281, 44389260321271340, 843395946104155461, 16024522975978953760, 304465936543600121441
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OFFSET
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0,3
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COMMENTS
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Partial sums of powers of 19 (A001029); q-integers for q=19: diagonal k=1 in triangle A022183.
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LINKS
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FORMULA
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a(n) = floor(19^n/18).
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MATHEMATICA
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PROG
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(Magma) [n le 2 select n-1 else 20*Self(n-1)-19*Self(n-2): n in [1..20]]; // Vincenzo Librandi, Nov 07 2012
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CROSSREFS
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Cf. similar sequences of the form (k^n-1)/(k-1): A000225, A003462, A002450, A003463, A003464, A023000, A023001, A002452, A002275, A016123, A016125, A091030, A135519, A135518, A131865, A091045, A218721, A064108, A218724-A218734, A132469, A218736-A218753, A133853, A094028, A218723.
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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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