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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.

A285038 a(n) = least k such that k*n belongs to A120383.

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%I A285038 #9 Apr 09 2017 10:30:44
%S A285038 1,1,2,1,6,1,4,1,2,3,30,1,6,2,2,1,28,1,8,3,4,15,18,1,6,3,2,1,30,1,330,
%T A285038 1,10,14,12,1,12,4,2,3,78,2,28,15,2,9,30,1,4,3,28,3,16,1,6,1,8,15,476,
%U A285038 1,18,165,4,1,6,5,152,7,6,6,60,1,84,6,2,2,60,1
%N A285038 a(n) = least k such that k*n belongs to A120383.
%C A285038 a(2*k+1) is even for any k > 0.
%H A285038 Rémy Sigrist, <a href="/A285038/b285038.txt">Table of n, a(n) for n = 1..10000</a>
%e A285038 5 = prime(3); as 5 is coprime to 3, a(5) must be a multiple of 3; 5*3 = prime(3)*prime(2) does not belong to A120383 as it is not divisible by 2; so a(5) must also be divisible by 2; 5*3*2 belongs to A120383, hence a(5) = 3*2 = 6.
%e A285038 7 = prime(4); as 7 is coprime to 4, a(7) must be a multiple of 4; 7*4 belongs to A120383, hence a(7)=4.
%o A285038 (PARI) complete(n) = my (c=n); my (f=factor(n)); for (i=1, #f~, c = lcm(c, primepi(f[i,1]))); return (c)
%o A285038 a(n) = my (m=n); while (1, my (mm=complete(m)); if (m==mm, return (m/n), m=mm))
%Y A285038 Cf. A120383.
%K A285038 nonn
%O A285038 1,3
%A A285038 _Rémy Sigrist_, Apr 08 2017