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A157196
a(n) = (1/2)*(sum of elements of n-th run) using 1 and 2 starting with 1,1.
3
1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1
OFFSET
1,3
COMMENTS
We conjecture that the density of 1's in the sequence approaches 2/3 as n -> infinity.
EXAMPLE
Write the sums of elements in each run, you obtain: 2,2,4,2,2,2,2,4,2,2,4,2,2,4,4,... dividing by 2 you get: 1,1,2,1,1,1,1,2,1,1,2,1,1,2,2,... the sequence itself.
MAPLE
mx:= 1000: l:= [1$2]: a:= n-> l[n]:
for h from 2 while nops(l)<mx do
t:= 2-irem(h, 2); l:= [l[], t$(l[h]*2/t)]
od:
seq (a(n), n=1..120); # Alois P. Heinz, May 31 2012
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 24 2009
EXTENSIONS
More terms from Alvin Hoover Belt, May 31 2012
STATUS
approved