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A B2-sequence due to Rachel Lewis.
2

%I #40 Jan 02 2020 09:28:00

%S 1,2,4,8,13,21,31,45,66,81,97,123,148,182,204,252,291,324,352,415,486,

%T 540,651,706,781,864,963,1003,1148,1217,1371,1409,1523,1673,1974,2105,

%U 2191,2317,2496,2652,2726,2858,3219,3268,3500,3605,3864,3962,4237

%N A B2-sequence due to Rachel Lewis.

%C "The first 68 elements of the sequence are [given], then the greedy algorithm is used." For this B2-sequence: "The reciprocal sum is at least 2.16086," greater than that of the Mian-Chowla sequence (A005282), which is at most 2.158533. - _Danny Rorabaugh_ (with quotes by Rachel Lewis), Sep 29 2015

%D Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 163-166, with section 2.20.2, Mian-Chowla and B2-Sequences

%H Danny Rorabaugh, <a href="/A046185/b046185.txt">Table of n, a(n) for n = 0..848</a>

%H Steven R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/constant/erdos/erdos.html">Erdos's Reciprocal Sum Constants</a> [Broken link]

%H Steven R. Finch, <a href="http://web.archive.org/web/20010620000306/http://www.mathsoft.com/asolve/constant/erdos/erdos.html">Erdos's Reciprocal Sum Constants</a> [From the Wayback machine]

%H Rachel Lewis, <a href="/A005282/a005282.pdf">Mian-Chowla and B2 sequences</a>, 1999. [Thanks to _Steven Finch_ for providing this document. Included with permission. - _N. J. A. Sloane_, Jan 02 2020]

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/B2-Sequence.html">B2 Sequence</a>

%F For n>67, a(n) is the least number such that all pairwise differences of distinct elements of {a(0), ..., a(n)} are distinct. - _Danny Rorabaugh_, Sep 29 2015

%Y Cf. A005282.

%K nonn

%O 0,2

%A _Eric W. Weisstein_

%E a(34) corrected by _Steven Finch_ in email with _Danny Rorabaugh_, Sep 29 2015