The tern sequence 
s(
n) is defined by 
s(0) = 0,
s(1) = 1, 
s(2
n) = 
s(
n),
s(2
n+1) = 
s(
n) + 
s(
n+1). Stern showed
in 1858 that gcd(
s(
n),
s(
n+1)) = 1,
and that every positive rational number
a/
b occurs exactly once in the form 
s(
n)/
s(
n+1)} for
some 
n ≥ 1.   We show that  in a strong sense, the
average value of these fractions is 3/2. We also show that 
for 
d ≥ 2, the pair (
s(
n), 
s(
n+1))
is uniformly distributed among all feasible pairs of congruence
classes modulo 
d. More precise results are presented for 
d = 2
and 3.
Full version:  pdf,   
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(Concerned with sequence
A002487.)
Received August 31 2008;
revised version received September 16 2008.
Published in Journal of Integer Sequences, September 16 2008.
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