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Search: id:A028352
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| A028352 |
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A Golomb-like recurrence that decreases infinitely often. |
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+0
1
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| 2, 8, 6, 4, 2, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 72, 70, 68, 66, 64, 62, 60, 58, 56, 54, 52, 50, 48, 46, 44, 42, 40, 38, 36, 34, 32, 30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 216, 214, 212, 210, 208, 206, 204, 202
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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The sequence is a solution to the recursion a(a(n)+n)=a(n)+4n which is similar to the Golomb recursion b(b(n)+kn)=2b(n)+kn, k=1,2...
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LINKS
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E. J. Barbeau, J. Chew and S. Tanny, A matrix dynamics approach to Golomb's recusion, Electronic J. Combinatorics, #4.1 16 1997.
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FORMULA
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a(1)=1, a(2*3^m+r)=8*3^m-2r with m=0, 1, 2..., 0<=r<=4*3^m-1. - Ralf Stephan (ralf(AT)ark.in-berlin.de), Jan 16 2003
a(n) = 12*3^floor(log(n/2)/log(3))-2*n - Benoit Cloitre (benoit7848c(AT)orange.fr), Jan 23 2003
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PROGRAM
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(PARI) a(n) = if(n==1, 2, m=floor(log(n/2)/log(3)):r=n-2*3^m:8*3^m-2*r)
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CROSSREFS
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Sequence in context: A016594 A019986 A146943 this_sequence A132699 A021353 A131361
Adjacent sequences: A028349 A028350 A028351 this_sequence A028353 A028354 A028355
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KEYWORD
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nonn,easy
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AUTHOR
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Simon Plouffe (simon.plouffe(AT)gmail.com)
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EXTENSIONS
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Edited by Ralf Stephan (ralf(AT)ark.in-berlin.de), Jan 16 2003
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