This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A334118 #11 Dec 28 2024 09:14:36 %S A334118 15,21,99,117,153,171,207,429,561,627,663,741,759,783,837,957,999, %T A334118 1023,1107,1161,1269,1431,1593,1647,1809,1917,1925,1971,2133,2275, %U A334118 2695,2975,3185,4235,5005,6545,6723,7209,7315,7735,7857,8091,8181,8343,8645,8667,8829,8855 %N A334118 Primitive terms of A334117: odd numbers m such that sigma(m, -1) >= 3/2 with no proper divisors sharing this property. %H A334118 Charles R Greathouse IV, <a href="/A334118/b334118.txt">Table of n, a(n) for n = 1..10000</a> %t A334118 Select[Range[1, 10^4, 2], DivisorSigma[-1, #] >= 3/2 && Max[DivisorSigma[-1, Most[Divisors[#]]]] < 3/2 &] (* _Amiram Eldar_, Dec 28 2024 *) %o A334118 (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 A334118 Cf. A334117, A000203, A005231, A119240. %K A334118 nonn %O A334118 1,1 %A A334118 _Charles R Greathouse IV_, Apr 14 2020