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a(n) = minimal positive k such that the concatenation of the binary expansions of n,n+1,...,n+k is divisible by n+k+1, or -1 if no such k exists.
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%I #42 Apr 24 2021 12:26:48

%S 1,6,253,160,23,6,577,14,1,4,383,8,1591,18,169,42,1879,210,57,20,69,

%T 1354,13,86,225,1532,577,300,13,30,6419,312,30639,12,151,8,89,2720,29,

%U 5830,1,1450,195,478,55,166528,127,1074,3559,252,41

%N a(n) = minimal positive k such that the concatenation of the binary expansions of n,n+1,...,n+k is divisible by n+k+1, or -1 if no such k exists.

%C A base 2 analog of A332580.

%C For n up to 1000 the presently unknown values are a(213) and a(743).

%H Joseph Myers, <a href="/A332563/b332563.txt">Table of n, a(n) for n = 1..212</a>

%H Joseph Myers, <a href="/A332563/a332563_1.txt">Table of n, a(n) for n = 1..1024</a>. The UNKNOWN entries at n = 213 and 743 are either -1 or greater than 10^9. [This extends an earlier table of Scott R. Shannon, which searched up to 128 with a search limit of 10^6.]

%H J. S. Myers, R. Schroeppel, S. R. Shannon, N. J. A. Sloane, and P. Zimmermann, <a href="http://arxiv.org/abs/2004.14000">Three Cousins of Recaman's Sequence</a>, arXiv:2004:14000 [math.NT], April 2020.

%H Scott R. Shannon, <a href="/A332586/a332586_1.txt">The quotient after the final division, for n = 1..15</a>

%H N. J. A. Sloane, <a href="https://vimeo.com/457349959">Conant's Gasket, Recamán Variations, the Enots Wolley Sequence, and Stained Glass Windows</a>, Experimental Math Seminar, Rutgers University, Sep 10 2020 (video of Zoom talk).

%Y Cf. A332580, A332584, A332586.

%K sign,base

%O 1,2

%A _Scott R. Shannon_ and _N. J. A. Sloane_, Feb 25 2020.