A285038 a(n) = least k such that k*n belongs to A120383.
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, 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, 1, 18, 165, 4, 1, 6, 5, 152, 7, 6, 6, 60, 1, 84, 6, 2, 2, 60, 1
Offset: 1
Keywords
Examples
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. 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.
Links
- Rémy Sigrist, Table of n, a(n) for n = 1..10000
Crossrefs
Cf. A120383.
Programs
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PARI
complete(n) = my (c=n); my (f=factor(n)); for (i=1, #f~, c = lcm(c, primepi(f[i,1]))); return (c) a(n) = my (m=n); while (1, my (mm=complete(m)); if (m==mm, return (m/n), m=mm))
Comments