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A003951
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G.f.: (1+x)/(1-8*x).
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55
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1, 9, 72, 576, 4608, 36864, 294912, 2359296, 18874368, 150994944, 1207959552, 9663676416, 77309411328, 618475290624, 4947802324992, 39582418599936, 316659348799488, 2533274790395904, 20266198323167232, 162129586585337856, 1297036692682702848
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Coordination sequence for infinite tree with valency 9.
Binomial transform is {1, 10, 91, 820, 7381, ...}, see A002452 . - Philippe DELEHAM (koloyoko(AT)lagoon.nc), Jul 22 2005
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LINKS
| INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 310
Index to divisibility sequences
Index to sequences with linear recurrences with constant coefficients, signature (8).
Index entries for sequences related to trees
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FORMULA
| a(n) = Sum_{ 0<=k<=n } A029653(n, k)*x^k for x = 7 . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Jul 10 2005
a(0)=1; for n>0, a(n)=9*8^(n-1). [From Vincenzo Librandi, Nov 18 2010]
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MAPLE
| k := 9; if n = 0 then 1 else k*(k-1)^(n-1); fi;
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MATHEMATICA
| q = 9; Join[{a = 1}, Table[If[n != 0, a = q*a - a, a = q*a], {n, 0, 25}]] (* and *) Join[{1}, 9*8^Range[0, 25]] (* From Vladimir Joseph Stephan Orlovsky, Jul 11 2011 *)
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CROSSREFS
| Sequence in context: A170594 A170642 A170690 * A033135 A127053 A001809
Adjacent sequences: A003948 A003949 A003950 * A003952 A003953 A003954
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KEYWORD
| nonn,easy
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AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
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EXTENSIONS
| Edited by N. J. A. Sloane (njas(AT)research.att.com), Dec 04 2009.
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