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Maximal possible numerator for a sum of the form 1 +/- 1/2 +/- 1/3 +/- ... +/- 1/n.
0

%I #9 Nov 20 2013 02:02:36

%S 1,3,11,25,137,127,949,2003,7129,7381,83711,86021,1145993,1171733,

%T 1195757,2436559,42142223,41461543,800021557,788381929,799467289,

%U 810048769,18863914247,19087007117,99182995801,100212655201,312536252003,315404588903

%N Maximal possible numerator for a sum of the form 1 +/- 1/2 +/- 1/3 +/- ... +/- 1/n.

%t nMax = 19; d = {0}; Table[d = Flatten[{d + 1/n, d - 1/n}]; Max[Abs[Numerator[d]]], {n, nMax}]

%Y Cf. A003418 (maximal denominator).

%Y Cf. A061195 (minimal numerator), A232090 (minimal denominator).

%K nonn

%O 1,2

%A _T. D. Noe_, Nov 19 2013