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A320272 Indices (starting at 0) of integers in the increasing sequence S of nonnegative numbers that are representable in base 3/2 with digits {0, 1, 2}. 1

%I

%S 0,1,3,6,11,17,25,34,46,60,77,96,117,142,169,200,232,268,308,353,401,

%T 453,508,568,631,699,771,847,929,1015,1108,1205,1308,1415,1527,1644,

%U 1767,1896,2029,2169,2315,2468,2626,2790,2961,3140,3325,3519,3719,3924,4138,4357,4585,4817,5057,5305,5561,5823,6094,6372,6658

%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, 1, 2}.

%C Base 3/2 representations are considered with nonnegative exponents only (i.e., ending at the radix point).

%C Odd-indexed terms of this sequence form A320035. The sequence S is essentially the same as in A320035 under multiplication of digits by 2 (i.e., under substitution H->1, 1->2).

%C a(n) is the number of positive numbers less than n that are representable in base 3/2 with digits {0, 1, 2}. - _Max Alekseyev_, Oct 12 2018

%F For all k >= 1, a(2*k-1) = A320035(k).

%e The sequence S starts with "0", "1"=1, "10"=3/2, "2", "100"=9/4, "11"=5/2, "20"=3, "101"=13/4, "1000"=27/8, ....

%e The indices of first four integers in S are a(1)=0, a(2)=1, a(3)=3, and a(4)=6.

%Y Cf. A320035.

%K base,nonn

%O 1,3

%A _Tanya Khovanova_ and PRIMES STEP Junior group, Oct 08 2018

%E Edited by _Max Alekseyev_, Oct 12 2018

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Last modified December 3 05:56 EST 2022. Contains 358512 sequences. (Running on oeis4.)