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A010903 Pisot sequence E(3,13), a(n)=[ a(n-1)^2/a(n-2)+1/2 ]. 1
3, 13, 56, 241, 1037, 4462, 19199, 82609, 355448, 1529413, 6580721, 28315366, 121834667, 524227237, 2255632184, 9705479209, 41760499493, 179686059838, 773148800711, 3326685824041, 14313982718072 (list; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

According to Boyd (Acta Arithm. 32 (1977) p 89), quoting Pisot, every E(3,.) sequence satisfies a linear recurrence of at most order 3. Here this is easily derived from the first terms of the sequence. Sequence equals A010920 for at least the first 32600 terms and maybe more. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 26 2008

For n>=1, a(n-1) is the number of generalized compositions of n when there are i+2 different types of i, (i=1,2,...). [From Milan R. Janjic (agnus(AT)blic.net), Sep 24 2010]

REFERENCES

D. W. Boyd, Some integer sequences related to the Pisot sequences, Acta Arithmetica, 34 (1979), 295-305.

D. W. Boyd, Linear recurrence relations for some generalized Pisot sequences, Advances in Number Theory ( Kingston ON, 1991) 333-340, Oxford Sci. Publ., Oxford Univ. Press, New York, 1993.

FORMULA

a(n)=5a(n-1)-3a(n-2) = 3*A116415(n)-2*A116415(n-1). O.g.f.: (3-2x)/(1-5x+3x^2). - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 26 2008

CROSSREFS

Sequence in context: A100588 A081952 * A010920 A095934 A151220 A151221

Adjacent sequences:  A010900 A010901 A010902 * A010904 A010905 A010906

KEYWORD

nonn

AUTHOR

Simon Plouffe (simon.plouffe(AT)gmail.com)

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Last modified February 16 19:48 EST 2012. Contains 205955 sequences.