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%I #31 Oct 12 2018 14:48:42
%S 0,3,11,25,46,77,117,169,232,308,401,508,631,771,929,1108,1308,1527,
%T 1767,2029,2315,2626,2961,3325,3719,4138,4585,5057,5561,6094,6658,
%U 7251,7880,8543,9245,9982,10760,11572,12419,13305,14226,15181,16177,17209,18285,19404,20560,21760,23007,24297,25637,27027
%N Indices (starting at 0) of integers in the increasing sequence S of nonnegative numbers that are representable in base 3/2 with digits {0, H=1/2, 1}.
%C Base 3/2 representations are considered with nonnegative exponents only (i.e. ending at the radix point).
%C Notice that this is not a positional number system as, for example, H0=3/4 < 1 (i.e., the lexicographical comparison of representations does not match the numerical comparison).
%C If we use base 3/2 with digits {0, 1, 2} instead (cf. A320272), this sequence correspond to the indices of even integers.
%F a(n) = number of positive numbers less than n that are representable in base 3/2 with digits {0, H=1/2, 1}. - _Max Alekseyev_, Oct 12 2018
%F a(n) = A320272(2*n-1).
%e The sequence S starts with 0, H=1/2, H0=3/4, 1, H00=9/8, HH=5/4, 10=3/2, H0H=13/8, H000=27/16, ....
%e The indices of first two integers in S are a(1)=0 and a(2)=3.
%Y Bisection of A320272.
%K base,nonn
%O 1,2
%A _Tanya Khovanova_ and PRIMES STEP Junior group, Oct 03 2018
%E Edited by _Max Alekseyev_, Oct 12 2018