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%I #8 Dec 09 2019 09:20:28
%S 4,8,14,16,21,22,25,26,28,32,35,38,42,44,49,50,52,55,56,62,64,69,70,
%T 74,76,81,82,84,87,88,91,93,94,98,100,104,110,112,115,117,118,121,122,
%U 124,128,133,134,138,140,143,145,146,148,152,155,158,161,162,164,168,171
%N Composite odious numbers.
%H Amiram Eldar, <a href="/A125495/b125495.txt">Table of n, a(n) for n = 1..10000</a>
%e 49 is in the sequence since it is composite and base-2 representation (110001) has an odd number of 1's.
%p a:=proc(n) local n2: n2:=convert(n,base,2): if add(n2[j],j=1..nops(n2)) mod 2 = 1 and isprime(n)=false then n else fi end: seq(a(n),n=2..210); # _Emeric Deutsch_, Jan 01 2007
%t Select[Range[171], OddQ @ DigitCount[#, 2][[1]] && CompositeQ[#] &] (* _Amiram Eldar_, Dec 09 2019 *)
%Y Intersection of A002808 (the composite numbers) and A000069 (odious numbers).
%K base,nonn
%O 1,1
%A _Tanya Khovanova_, Dec 27 2006
%E More terms from _Emeric Deutsch_, Jan 01 2007