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A specially constructed B_2 sequence with sum of reciprocals greater than that of the Mian-Chowla sequence A005282.
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%I #5 Jul 11 2015 13:25:21

%S 1,2,4,8,13,21,31,45,66,81,97,123,148,182,229,257,290,312,381,419,467,

%T 507,621,721,770,864,927,1050,1178,1289,1457,1561,1615,1774,1907,2090,

%U 2164,2263,2309,2539,2800,2938,3035,3310,3380,3738,4043,4239,4439,4726,4851,5016,5169,5289,5490,5760,6646,6843,7015,7442,7674,7986,8284,8506,8772,9240,9778,9996,10344,10431,11614,12263

%N A specially constructed B_2 sequence with sum of reciprocals greater than that of the Mian-Chowla sequence A005282.

%C Constructed using the greedy algorithm (as for A005252) except at 15th term, which is 229.

%C It had been conjectured that the sum of reciprocals for B_2 sequences was maximized by A005282. This sequence gives a counterexample.

%H Zhang Zhen-Xiang, <a href="http://dx.doi.org/10.1090/S0025-5718-1993-1181334-7">A B_2-sequence with larger reciprocal sum</a>, Math. Comp. 60 (1993), 835-839.

%Y Cf. A005282.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Jul 11 2015