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%I #11 Dec 28 2024 09:14:36
%S 15,21,99,117,153,171,207,429,561,627,663,741,759,783,837,957,999,
%T 1023,1107,1161,1269,1431,1593,1647,1809,1917,1925,1971,2133,2275,
%U 2695,2975,3185,4235,5005,6545,6723,7209,7315,7735,7857,8091,8181,8343,8645,8667,8829,8855
%N Primitive terms of A334117: odd numbers m such that sigma(m, -1) >= 3/2 with no proper divisors sharing this property.
%H Charles R Greathouse IV, <a href="/A334118/b334118.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[1, 10^4, 2], DivisorSigma[-1, #] >= 3/2 && Max[DivisorSigma[-1, Most[Divisors[#]]]] < 3/2 &] (* _Amiram Eldar_, Dec 28 2024 *)
%o (PARI) list(lim)=my(v=List(), k); forfactored(n=15,lim\1, if(sigma(n,-1)>=3/2 && (k=n[1])%2, for(i=1,#v, if(k%v[i]==0, next(2))); listput(v,k))); Vec(v)
%Y Cf. A334117, A000203, A005231, A119240.
%K nonn
%O 1,1
%A _Charles R Greathouse IV_, Apr 14 2020