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A065694
Braided power sequence: A065692 is b(n+1)=3b(n)+2d(n)-c(n), A065693 is c(n+1)=3c(n)+2b(n)-d(n) and this is d(n+1)=3d(n)+2c(n)-b(n), starting with b(0)=0, c(0)=1 and d(0)=2.
2
2, 8, 23, 47, 80, 365, 3089, 19916, 96287, 369983, 1188008, 3489557, 11440865, 49588820, 250207799, 1210364111, 5215038272, 20004134333, 70879879793, 248964475292, 941859229775, 3946659132575, 17384730325784, 75199501505381
OFFSET
0,1
COMMENTS
Tends to 4^n. "Braided" because the order of b(n), c(n) and d(n) changes between the six possibilities as n increases.
FORMULA
Conjectures from Colin Barker, Sep 02 2016: (Start)
a(n) = 9*a(n-1)-33*a(n-2)+52*a(n-3) for n>2.
G.f.: (2-10*x+17*x^2) / ((1-4*x)*(1-5*x+13*x^2)).
(End)
EXAMPLE
a(1) = 3*2+2*1-1*0 = 8.
CROSSREFS
Sequence in context: A303287 A321068 A158466 * A178129 A203298 A161463
KEYWORD
nonn
AUTHOR
Henry Bottomley, Nov 14 2001
STATUS
approved