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Positions of 1 in A188068; complement of A188069.
5

%I #30 Dec 18 2023 12:12:03

%S 2,3,5,6,7,9,10,11,13,14,16,17,18,20,21,22,24,25,26,28,29,31,32,33,35,

%T 36,37,39,40,41,43,44,46,47,48,50,51,52,54,55,57,58,59,61,62,63,65,66,

%U 67,69,70,72,73,74,76,77,78,80,81,82,84,85,87,88,89,91,92,93,95,96,97,99,100,102,103,104,106,107,108,110,111,113,114,115,117,118,119,121,122,123,125

%N Positions of 1 in A188068; complement of A188069.

%C Cf. A188014, A188068.

%C Also positions of 3 in A007538. - _Reinhard Zumkeller_, Feb 14 2012

%C From _Peter G. Anderson_, Aug 24 2012: (Start)

%C a(n) = ceiling(n*x) where x = (1+sqrt(3))/2;

%C continued fraction of x is [1,2,1,2,1,2,...]. (End)

%C Conjectured partial sums of A245222. - _Sean A. Irvine_, Jun 26 2022

%t (See A188068.)

%o (Haskell)

%o a188070 n = a188070_list !! (n-1)

%o a188070_list = filter ((== 3) . a007538) [1..]

%o -- _Reinhard Zumkeller_, Feb 14 2012

%o (J) >. (2 %~ 1 + %:3) * i.100 NB. _Peter G. Anderson_, Aug 24 2012

%Y Cf. A188014, A188068, A188069.

%Y A215781 is ceiling(n*(sqrt(3)-1)).

%K nonn

%O 1,1

%A _Clark Kimberling_, Mar 20 2011