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A079450
a(n) = 2^(n-1)*u(n) where u(1)=1 and u(n) = frac(3/2*u(n-1)) + 1.
1
1, 3, 5, 15, 29, 55, 101, 175, 269, 807, 1397, 2143, 6429, 11095, 16901, 50703, 86573, 259719, 517013, 1026751, 2031677, 3997879, 7799333, 15009391, 28250957, 51198439, 86486453, 259459359, 509942621, 992956951, 1905129029, 3567903439
OFFSET
1,2
LINKS
FORMULA
a(n+1)<=3*a(n). Conjecture : a(n+1)=3*a(n) if and only if n is a greedy power of (2/3) (i.e. n is in A077468)
MATHEMATICA
u[1]:= 1; u[n_]:= u[n]= FractionalPart[3*u[n-1]/2] +1; a[n_]:= 2^(n-1)* u[n]; Table[a[n], {n, 1, 40}] (* G. C. Greubel, Jan 18 2019 *)
CROSSREFS
Sequence in context: A284031 A284410 A118173 * A284482 A166956 A048738
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jan 13 2003
STATUS
approved