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Square array A(n, k), n, k >= 0, read and filled by upwards antidiagonals the greedy way with distinct nonnegative integers such that the binary expansions of any two distinct terms in the same row or column or antidiagonal have no common 1's.
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%I #11 Oct 08 2023 09:00:27

%S 0,1,2,4,8,16,10,17,32,64,48,68,128,256,9,192,512,257,34,20,1024,768,

%T 1056,6,144,2048,4096,8192,3072,4224,520,8193,16384,320,32768,36,

%U 12288,16640,1088,2052,32896,544,65536,131072,262144,49152,67584,135168,262152,258,524288,1048576,1536,8256,2097152

%N Square array A(n, k), n, k >= 0, read and filled by upwards antidiagonals the greedy way with distinct nonnegative integers such that the binary expansions of any two distinct terms in the same row or column or antidiagonal have no common 1's.

%C This sequence is a variant of A366030; here we avoid common 1's in binary expansions, there common prime factors.

%C All the powers of 2 appear in the sequence, in ascending order.

%C For any k >= 0, the first term of the sequence whose binary expansion contains 2^k is 2^k.

%C Will every nonnegative integer appear in the sequence?

%H Rémy Sigrist, <a href="/A366031/a366031.png">Colored representation of the array for n, k <= 673</a> (grayish pixels correspond to powers of 2)

%H Rémy Sigrist, <a href="/A366031/a366031.gp.txt">PARI program</a>

%e Array A(n, k) begins:

%e n\k| 1 2 3 4 5 6 7 8

%e ---+-----------------------------------------------------------------

%e 1| 0 2 16 64 9 1024 8192 36

%e 2| 1 8 32 256 20 4096 32768 131072

%e 3| 4 17 128 34 2048 320 65536 1536

%e 4| 10 68 257 144 16384 544 1048576 6144

%e 5| 48 512 6 8193 32896 524288 72 4194560

%e 6| 192 1056 520 2052 258 2097153 20480 32784

%e 7| 768 4224 1088 262152 1048608 18 2049 67117056

%e 8| 3072 16640 135168 33280 65600 12 50 129

%o (PARI) See Links section.

%Y Cf. A366030.

%K nonn,base,tabl

%O 0,3

%A _Rémy Sigrist_, Sep 26 2023