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%I #18 Mar 09 2023 13:02:37
%S 2,4,8,14,16,22,26,28,32,38,42,44,50,52,56,62,64,70,74,76,82,84,88,94,
%T 98,100,104,110,112,118,122,124,128,134,138,140,146,148,152,158,162,
%U 164,168,174,176,182,186,188,194,196,200,206,208,214,218,220,224,230,234,236,242
%N a(n) = 2*A000069(n).
%C These are the even odious numbers. - _Tanya Khovanova_, May 15 2007
%H Charles R Greathouse IV, <a href="/A128309/b128309.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 4n + O(1). - _Charles R Greathouse IV_, Mar 22 2013
%t Select[Range[2,300,2],OddQ[DigitCount[#,2,1]]&] (* _Harvey P. Dale_, Oct 08 2017 *)
%o (PARI) is(n)=n%2==0 && hammingweight(n)%2 \\ _Charles R Greathouse IV_, Mar 22 2013
%o (PARI) a(n)=4*n-if(hammingweight(n-1)%2,4,2) \\ _Charles R Greathouse IV_, Mar 22 2013
%o (Python)
%o def A128309(n): return ((m:=n-1)<<1)+(m.bit_count()&1^1)<<1 # _Chai Wah Wu_, Mar 09 2023
%Y Different from A074202.
%Y Intersection of A000069 (odious numbers: odd number of 1's in binary expansion) and A005843 (even numbers).
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_, May 10 2007