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 A230095 #18 May 21 2024 16:41:44 %S A230095 14,21,22,26,35,38,55,62,69,74,82,87,91,93,94,115,118,122,133,134,143, %T A230095 145,146,155,158,161,185,194,203,205,206,213,214,217,218,247,253,254, %U A230095 259,262,265,274,295,299,301,302,309,314,319,321,327,334,339,341,346 %N A230095 Odious numbers (A000069) that are the product of exactly two distinct primes. %H A230095 Charles R Greathouse IV, <a href="/A230095/b230095.txt">Table of n, a(n) for n = 1..10000</a> %H A230095 E. Fouvry, C. Mauduit, <a href="http://dx.doi.org/10.1007/BF01444238">Sommes des chiffres et nombres presque premiers</a>, (French) [Sums of digits and almost primes] Math. Ann. 305 (1996), no. 3, 571--599. MR1397437 (97k:11029). %t A230095 Select[Range[400],OddQ[DigitCount[#,2,1]]&&PrimeNu[#]==PrimeOmega[#]==2&] (* _Harvey P. Dale_, May 21 2024 *) %o A230095 (PARI) isodious(n)=b = binary(n); sum(i=1, #b, b[i]==1) % 2; %o A230095 isok(n) = isodious(n) && (bigomega(n)==2) && (omega(n)==2); \\ _Michel Marcus_, Oct 12 2013 %o A230095 (PARI) list(lim)=my(v=List()); forprime(p=2,lim\2, forprime(q=2,min(lim\p,p-1), if(hammingweight(p*q)%2, listput(v,p*q)))); Set(v) \\ _Charles R Greathouse IV_, Jan 31 2017 %Y A230095 Cf. A000069, A027697, A130593. %K A230095 nonn,base %O A230095 1,1 %A A230095 _N. J. A. Sloane_, Oct 11 2013 %E A230095 More terms from _Michel Marcus_, Oct 12 2013