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A018907 Define the sequence S(a_0,a_1) by a_{n+2} is the least integer such that a_{n+2}/a_{n+1} > a_{n+1}/a_n for n >= 0. This is S(2,7). 1
2, 7, 25, 90, 325, 1174, 4241, 15321, 55349, 199956, 722370, 2609667, 9427803, 34059315, 123044249, 444515318, 1605876501, 5801463374, 20958633656, 75716124779, 273535557978, 988187148996, 3569970385786, 12897039359739, 46592438107869, 168321986797406 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1000

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.

MAPLE

a:= proc(n) option remember; `if`(n<2, [2, 7][n+1],

       1 +floor(a(n-1)^2/a(n-2)))

    end:

seq(a(n), n=0..40);  # Alois P. Heinz, May 05 2014

PROG

(PARI) S(a0, a1, maxn) = a=vector(maxn); a[1]=a0; a[2]=a1; for(n=3, maxn, a[n]=a[n-1]^2\a[n-2]+1); a

S(2, 7, 40) \\ Colin Barker, Feb 16 2016

CROSSREFS

Sequence in context: A007484 A070859 A048576 * A052936 A108152 A024482

Adjacent sequences:  A018904 A018905 A018906 * A018908 A018909 A018910

KEYWORD

nonn

AUTHOR

R. K. Guy, Dec 11 1996

STATUS

approved

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Last modified January 22 09:52 EST 2019. Contains 319363 sequences. (Running on oeis4.)