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A218739
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a(n) = (36^n - 1)/35.
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3
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0, 1, 37, 1333, 47989, 1727605, 62193781, 2238976117, 80603140213, 2901713047669, 104461669716085, 3760620109779061, 135382323952046197, 4873763662273663093, 175455491841851871349, 6316397706306667368565, 227390317427040025268341, 8186051427373440909660277
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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 36 (A009980).
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LINKS
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FORMULA
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G.f.: x/((1 - x)*(1 - 36*x)).
a(n) = 37*a(n-1) - 36*a(n-2).
a(n) = floor(36^n/35). (End)
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MATHEMATICA
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Join[{0}, Accumulate[36^Range[0, 20]]] (* Harvey P. Dale, Jun 03 2015 *)
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PROG
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(Magma) [n le 2 select n-1 else 37*Self(n-1)-36*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, A218722, 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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