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 A126283 #11 Feb 07 2020 21:09:02
%S A126283 4,18,40,76,116,182,246,330,426,532,652,770,904,1058,1210,1386,1560,
%T A126283 1752,1956,2162,2394,2640,2894,3150,3422,3680,3984,4302,4628,4974,
%U A126283 5294,5650,5914,6006,6372,6746,7146,7536,7938,8386,8794,9222,9702,10156
%N A126283 Largest number k for which the n-th prime is the median of the largest prime dividing the first k integers.
%C A126283 a(14) = 1058 is the first term where a(n) exceeds A290154(n). - _Peter Munn_, Aug 02 2019
%e A126283 a(1)=4 because the median of {2,3,2} = {2, *2*,3} is 2 (the * surrounds the median) and for any number greater than 4 the median is greater than 2.
%e A126283 a(1)=18 because the median of {2,3,2,5,3,7,2,3,5,11,3,13,7,5,2,17,3} = {2,2,2,2,3,3,3,3, *3*,5,5,5,7,7,11,13,17}.
%t A126283 t = Table[0, {100}]; lst = {}; Do[lpf = FactorInteger[n][[ -1, 1]]; AppendTo[lst, lpf]; mdn = Median@lst; If[PrimeQ@ mdn, t[[PrimePi@mdn]] = n], {n, 2, 10^4}]; t
%Y A126283 Other sequences about medians of prime factors: A124202, A126282, A281889, A284411, A290154, A308904.
%Y A126283 Cf. A000040, A309366.
%K A126283 nonn
%O A126283 1,1
%A A126283 Mark Thornquist (mthornqu(AT)fhcrc.org) & _Robert G. Wilson v_, Dec 15 2006