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 A385486 #18 Aug 09 2025 15:15:09
%S A385486 1,2,12,126,252,504,2040,4080,16380,32760,65520,524286,1048572,
%T A385486 4194300,8388600,134217720,268435440,7516192740,10737418230,
%U A385486 21474836460,137438953440,274877906880,274877906940,549755813880,8796093022200,8796093022206,17592186044412
%N A385486 Where records occur in A385485.
%H A385486 Chai Wah Wu, <a href="/A385486/b385486.txt">Table of n, a(n) for n = 1..27</a>
%F A385486 A385485(a(n)) = A385487(n).
%t A385486 f[n_] := Module[{m = n, k = 1}, While[Divisible[m, DigitSum[m, 2]], m += 2*n; k += 2]; k];
%t A385486 seq[lim_] := Module[{s = {}, fm = -1, fi}, Do[fi = f[i]; If[fi > fm, fm = fi; AppendTo[s, i]], {i, 1, lim}]; s]; seq[10^4]
%o A385486 (PARI) f(n) = {my(m = n, k = 1); while(!(m % hammingweight(m)), m += 2*n; k += 2); k;}
%o A385486 list(lim) = my(fm = -1, fi); for(i = 1, lim, fi = f(i); if(fi > fm, fm = fi; print1(i, ", ")));
%Y A385486 Cf. A049445, A144376 (decimal analog), A385483, A385485, A385487 (record values).
%K A385486 nonn,base
%O A385486 1,2
%A A385486 _Amiram Eldar_, Jun 30 2025
%E A385486 a(21)-a(27) from _Chai Wah Wu_, Jul 02 2025