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A291357
The arithmetic function u(n,2,3).
1
4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3, 2, 4, 2, 4, 2, 3
OFFSET
1,1
LINKS
Bela Bajnok, Additive Combinatorics: A Menu of Research Problems, arXiv:1705.07444 [math.NT], May 2017. See Table in Section 1.6.3.
MATHEMATICA
u[n_, m_, h_] := (d = Divisors[n]; Min[(h*Ceiling[m/d] - h + 1)*d]); Table[u[n, 2, 3], {n, 1, 70}]
PROG
(PARI) A291357(n, m=2, h=3) = { my(p=0, k); fordiv(n, d, k = d*(h*ceil(m/d) - h + 1); if(!p || (k < p), p = k)); (p); }; \\ Antti Karttunen, Oct 01 2018
KEYWORD
nonn
AUTHOR
Robert Price, Aug 23 2017
EXTENSIONS
More terms from Antti Karttunen, Oct 01 2018
STATUS
approved