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A018921 Define the sequence T(a_0,a_1) by a_{n+2} is the greatest integer such that a_{n+2}/a_{n+1}<a_{n+1}/a_n for n >= 0. This is T(4,8). 3
4, 8, 15, 28, 52, 96, 177, 326, 600, 1104, 2031, 3736, 6872, 12640, 23249, 42762, 78652, 144664, 266079, 489396, 900140, 1655616, 3045153, 5600910, 10301680 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

a(n) = A008937(n+2) = A027084(n+3)+1.

REFERENCES

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;.

LINKS

Table of n, a(n) for n=0..24.

FORMULA

Probably satisfies a(n) = 2*a(n-1) - a(n-4).

Empirical G.f.: (4-x^2-2*x^3)/(1-2*x+x^4). [Colin Barker, Feb 08 2012]

CROSSREFS

Cf. A008937.

Sequence in context: A024624 A098196 A027961 * A103536 A011970 A111988

Adjacent sequences:  A018918 A018919 A018920 * A018922 A018923 A018924

KEYWORD

nonn

AUTHOR

R. K. Guy

STATUS

approved

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Last modified November 26 11:07 EST 2014. Contains 250056 sequences.