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n appears A070939(n) times.
6

%I #20 Feb 18 2024 01:31:27

%S 0,1,2,2,3,3,4,4,4,5,5,5,6,6,6,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,11,

%T 11,11,11,12,12,12,12,13,13,13,13,14,14,14,14,15,15,15,15,16,16,16,16,

%U 16,17,17,17,17,17,18,18,18,18,18,19,19,19,19,19,20,20,20,20,20,21,21,21

%N n appears A070939(n) times.

%H Reinhard Zumkeller, <a href="/A030530/b030530.txt">Table of n, a(n) for n = 0..10000</a>

%F A030190(n) = T(a(n), A083652(a(n))-n-1), T as defined in A083651.

%F a(A083652(k)) = k+1.

%F Sum_{n>=1} (-1)^(n+1)/a(n) = Sum_{n>=1} (-1)^(n+1)/A053738(n) = 0.90457767... . - _Amiram Eldar_, Feb 18 2024

%t Join[{0},Table[Table[n,IntegerLength[n,2]],{n,30}]]//Flatten (* _Harvey P. Dale_, Oct 20 2016 *)

%o (Haskell)

%o import Data.List (unfoldr)

%o a030530 n = a030530_list !! (n-1)

%o a030530_list = 0 : concatMap (\n -> unfoldr

%o (\x -> if x == 0 then Nothing else Just (n, div x 2)) n) [1..]

%o -- _Reinhard Zumkeller_, Dec 05 2011

%Y Cf. A030190, A053738, A070939, A083651, A083652.

%K easy,nonn

%O 0,3

%A _J. Lowell_