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 A001284 #23 Feb 11 2025 20:33:39 %S A001284 6,12,15,20,24,28,30,35,40,42,45,48,54,56,60,63,66,70,72,77,80,84,88, %T A001284 90,91,96,99,104,108,110,112,117,120,126,130,132,135,140,143,144,150, %U A001284 153,154,156,160,165,168,170,176,180,182,187,190,192,195,198,204,208,209,210,216,220,221,224,228,231 %N A001284 Numbers of form m*k with m+1 <= k <= 2m-1. %H A001284 Charles R Greathouse IV, <a href="/A001284/b001284.txt">Table of n, a(n) for n = 1..10000</a> %o A001284 (PARI) list(lim)=my(v=List()); for(m=2,sqrt(lim), for(k=m+1,min(lim\m,2*m-1), listput(v,m*k))); Set(v) \\ _Charles R Greathouse IV_, Oct 23 2015 %Y A001284 Subsequence of A005279. %K A001284 nonn,easy %O A001284 1,1 %A A001284 _N. J. A. Sloane_ %E A001284 Terms a(45) and beyond, and offset corrected by _Charles R Greathouse IV_, Oct 23 2015