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A132679 Starting with a(1)=1 and a(2)=2: if m is a term then also 4*m and 4*m+3.

%I A132679 #15 Feb 16 2025 08:33:06
%S A132679 1,2,4,7,8,11,16,19,28,31,32,35,44,47,64,67,76,79,112,115,124,127,128,
%T A132679 131,140,143,176,179,188,191,256,259,268,271,304,307,316,319,448,451,
%U A132679 460,463,496,499,508,511,512,515,524,527,560,563,572,575,704,707,716
%N A132679 Starting with a(1)=1 and a(2)=2: if m is a term then also 4*m and 4*m+3.
%C A132679 Subsequence of A000069; A010060(a(n))=1; A000120(a(n)) mod 2 = 1;
%C A132679 A000079, A083420, A002042, A002089 are subsequences.
%H A132679 Reinhard Zumkeller, <a href="/A132679/b132679.txt">Table of n, a(n) for n = 1..10000</a>
%H A132679 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/OdiousNumber.html">Odious Number</a>
%H A132679 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%t A132679 Union[Nest[Flatten[{#,4#,4#+3}]&,{1,2},4]] (* _Harvey P. Dale_, Aug 02 2013 *)
%o A132679 (Haskell)
%o A132679 import Data.Set (fromList, insert, deleteFindMin)
%o A132679 a132679 n = a132679_list !! (n-1)
%o A132679 a132679_list = f $ fromList [1,2] where
%o A132679    f s = m : f (insert (4*m) $ insert (4*m+3) s') where
%o A132679        (m,s') = deleteFindMin s
%o A132679 -- _Reinhard Zumkeller_, Oct 29 2011
%Y A132679 Cf. A179888. [From _Reinhard Zumkeller_, Jul 31 2010]
%K A132679 nonn
%O A132679 1,2
%A A132679 _Reinhard Zumkeller_, Aug 26 2007