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%I #15 May 21 2024 14:14:36
%S 30,42,66,70,78,102,110,114,130,138,154,170,174,182,186,190,222,230,
%T 238,246,258,266,282,286,290,310,318,322,354,366,370,374,402,406,410,
%U 418,426,430,434,438,442,470,474,494,498,506,518,530,534,574,582,590
%N Squarefree even composite numbers with an odd number of prime factors.
%C Prime factors counted with multiplicity. - _Harvey P. Dale_, May 21 2024
%H Charles R Greathouse IV, <a href="/A053858/b053858.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3)=66 because 66 is even and its prime divisors are 2, 3 and 11, an odd number.
%p ts_m2_sod := proc(n); if (numtheory[mobius](n)=-1 and isprime(n)='false' and type(n,even)='true') then RETURN(n); fi end: am2sod := [seq(ts_m2_sod(i), i=1..2500)]: am2sod;
%t Select[Range[2,602,2],CompositeQ[#]&&SquareFreeQ[#]&&OddQ[PrimeOmega[#]]&] (* _Harvey P. Dale_, May 21 2024 *)
%o (PARI) is(n,f=factor(n))=n%2==0 && #f[,2]>2 && vecmax(f[,2])==1 && (#f[,2])%2 \\ _Charles R Greathouse IV_, Aug 29 2017
%Y A075819 is a subsequence. Intersection of A026424, A039956, and A002808.
%K easy,nonn
%O 1,1
%A _Enoch Haga_, Mar 28 2000
%E Name corrected by _Charles R Greathouse IV_, Aug 29 2017
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