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 A303770 #7 May 06 2018 00:49:37
%S A303770 1,2,6,3,15,5,10,30,210,42,21,7,14,70,35,105,1155,165,55,11,22,66,33,
%T A303770 231,77,154,462,2310,330,110,770,385,5005,455,91,13,26,78,39,195,65,
%U A303770 130,390,2730,182,546,273,1365,15015,3003,429,143,286,858,4290,1430,715,2145,36465,561,51,17,34,102,510,170,85,255,1785,357,119,238,714
%N A303770 Divisor-or-multiple permutation of squarefree numbers: a(n) = A019565(A303773(n)).
%C A303770 Each a(n+1) is either a divisor or a multiple of a(n).
%H A303770 Antti Karttunen, <a href="/A303770/b303770.txt">Table of n, a(n) for n = 0..10092</a>
%F A303770 a(n) = A019565(A303773(n)).
%o A303770 (PARI)
%o A303770 A019565(n) = {my(j,v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
%o A303770 A303770(n) = A019565(A303773(n)); \\ Uses also code from A303773.
%Y A303770 Cf. A005117, A019565, A303773.
%Y A303770 Cf. A303760 (a simpler variant).
%K A303770 nonn
%O A303770 0,2
%A A303770 _Antti Karttunen_, May 05 2018