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%I #9 Mar 18 2018 04:08:49
%S 1,1,1,1,7,3,11,13,11,11,23,23,607,251,251,125,97,97,3767,3767,3767,
%T 2285,24319,24319,71559,4261,13703,13703,872843,872843,17424097,
%U 13828799,902339,7850449,7850449,7850449,10683197,68185267,37728713,37728713,740674333
%N Minimum positive value of lcm{1,...,n}*(s_1/1 + ... + s_n/n), where each s_i equals 1 or -1.
%C Nonnegative by considering the largest power of 2 up to n.
%e 1/1 - 1/2 - 1/3 - 1/4 - 1/5 + 1/6 + 1/7 = 11/420 = 11/lcm(1,2,3,4,5,6,7), so a(7) <= 11; no other choice of signs yields 1/420, ..., 10/420, so a(7)=11.
%Y See also A061195.
%K nonn
%O 1,5
%A Greg Martin (gerg(AT)math.toronto.edu), Apr 19 2001
%E More terms from _Naohiro Nomoto_, Jun 24 2001
%E a(23)-a(41) from _Giovanni Resta_, Jun 12 2016