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%I #13 Jul 25 2020 12:16:47
%S 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 1024,516,192,1280,2048,4096,9,130,1536,288,2112,4100,8192,514,160,
%U 6144,16384,32768,13,1152,768,10240,20480,65536,18,32800,12288,2304,640
%N 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 We can always extend the sequence with a power of 2 greater than any previous term, so the sequence is well defined.
%C 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 Rémy Sigrist, <a href="/A336350/b336350.txt">Table of n, a(n) for n = 0..10200</a>
%H 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 Rémy Sigrist, <a href="/A336350/a336350.gp.txt">PARI program for A336350</a>
%e The spiral begins:
%e 264------80--262144---81920----5120---32896----2560----8224-------7
%e | |
%e 49152 8192----4100----2112-----288----1536-----130-------9 65552
%e | | | |
%e 3072 514 256-----128------72------48-------5 4096 131072
%e | | | | | |
%e 4608 160 17 8-------4-------2 64 2048 17408
%e | | | | | | | |
%e 73728 6144 96 6 0-------1 24 1280 640
%e | | | | | | |
%e 393216 16384 512 16-------3------12------32 192 2304
%e | | | | |
%e 524288 32768 10------33-----144-----320----1024-----516 12288
%e | | |
%e 1048576 13----1152-----768---10240---20480---65536------18---32800
%e |
%e 19---65792---18432----9216---33280--655360--266240-2097152-1048584
%o (PARI) See Links section.
%Y See A336349 for a similar sequence.
%K nonn,look,base
%O 0,3
%A _Rémy Sigrist_, Jul 19 2020