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Variant of A332563 - binary version of Recamán concatenation sequence.
1

%I #48 Jan 09 2021 21:05:34

%S 2,1,3,3,2,1,8,4,6,3,2,3,2,1,3,15,10,13,4,3,10,9,8,7,6,5,4,3,2,1,8,7,

%T 27,29,28,27,26,10,24,23,22,21,20,19,3,15,14,15,14,13,12,3,10,9,8,7,6,

%U 5,4,3,2,1,16,15,62,13,2,27,58,16,15,55,22,2,52,51,2,36,16,3,46,33,7,43,2,5,3,23,38,33,4,3,34,33,13,7,22,29,16,3,26,22,16,7,22,17,2,3,2,17,16,9,14,13,12,11,10,9,8,7,6,5,4,3,2,1,128

%N Variant of A332563 - binary version of Recamán concatenation sequence.

%C Inspired by Neil Sloane's presentation at Rutgers' Experimental Mathematics Seminar (see the Links section).

%C In the original version (A332563), for a given n, one concatenate the binary representation of n||n+1||n+2||...||n+i until the corresponding number is divisible by n+i+1.

%C In this variant, one skips n+1 as an ingredient of the concatenation.

%C A337137(n) records the least i such that n||n+2||n+3||...||n+i is divisible by n+i+1.

%C This version is tamer than the one in A332563.

%C The scatterplot graph shows some interesting structures.

%H Olivier Gérard, <a href="/A337137/b337137.txt">Table of n, a(n) for n = 1..2048</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).

%t Module[{s, i, imax = 128},

%t Table[ s = IntegerDigits[n, 2]; i = 0;

%t While[Mod[FromDigits[s, 2], n + i + 1] > 0 && i <= imax, i = i + 1;

%t s = Join[s, IntegerDigits[n + i + 1, 2]]];

%t i /. {imax + 1 -> Infinity} , {n, 1, 127}]]

%Y Cf. A332580, A332563.

%K nonn,look,base

%O 1,1

%A _Olivier Gérard_, Sep 14 2020