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A336350 Square spiral of distinct nonnegative integers constructed by greedy algorithm, such that two terms on the same row or on the same column have no common one bit in their binary representations.

%I A336350 #13 Jul 25 2020 12:16:47
%S A336350 0,1,2,4,8,6,16,3,12,32,24,64,5,48,72,128,256,17,96,512,10,33,144,320,
%T A336350 1024,516,192,1280,2048,4096,9,130,1536,288,2112,4100,8192,514,160,
%U A336350 6144,16384,32768,13,1152,768,10240,20480,65536,18,32800,12288,2304,640
%N A336350 Square spiral of distinct nonnegative integers constructed by greedy algorithm, such that two terms on the same row or on the same column have no common one bit in their binary representations.
%C A336350 We can always extend the sequence with a power of 2 greater than any previous term, so the sequence is well defined.
%C A336350 For symmetry reasons, we obtain the same sequence when considering a clockwise or a counterclockwise square spiral, or when initially moving towards any unit direction.
%H A336350 Rémy Sigrist, <a href="/A336350/b336350.txt">Table of n, a(n) for n = 0..10200</a>
%H A336350 Rémy Sigrist, <a href="/A336350/a336350.png">Colored representation of the spiral for -250 <= x <= 250 and -250 <= y <= 250</a> (where the hue is function of a(n) and black pixels indicate powers of 2)
%H A336350 Rémy Sigrist, <a href="/A336350/a336350.gp.txt">PARI program for A336350</a>
%e A336350 The spiral begins:
%e A336350          264------80--262144---81920----5120---32896----2560----8224-------7
%e A336350            |                                                               |
%e A336350        49152    8192----4100----2112-----288----1536-----130-------9   65552
%e A336350            |       |                                               |       |
%e A336350         3072     514     256-----128------72------48-------5    4096  131072
%e A336350            |       |       |                               |       |       |
%e A336350         4608     160      17       8-------4-------2      64    2048   17408
%e A336350            |       |       |       |               |       |       |       |
%e A336350        73728    6144      96       6       0-------1      24    1280     640
%e A336350            |       |       |       |                       |       |       |
%e A336350       393216   16384     512      16-------3------12------32     192    2304
%e A336350            |       |       |                                       |       |
%e A336350       524288   32768      10------33-----144-----320----1024-----516   12288
%e A336350            |       |                                                       |
%e A336350      1048576      13----1152-----768---10240---20480---65536------18---32800
%e A336350            |
%e A336350           19---65792---18432----9216---33280--655360--266240-2097152-1048584
%o A336350 (PARI) See Links section.
%Y A336350 See A336349 for a similar sequence.
%K A336350 nonn,look,base
%O A336350 0,3
%A A336350 _Rémy Sigrist_, Jul 19 2020