1, 2, 3, 4, 6, 5, 8, 12, 10, 15, 16, 24, 20, 30, 17, 32, 48, 40, 60, 34, 51, 64, 96, 80, 120, 68, 102, 85, 128, 192, 160, 240, 136, 204, 170, 255, 256, 384, 320, 480, 272, 408, 340, 510, 257, 512, 768, 640, 960, 544, 816, 680, 1020, 514, 771, 1024, 1536, 1280, 1920
Offset: 0
The main diagonal equals A001317 (Pascal's triangle mod 2 in decimal):
{1,3,5,15,17,51,85,255,257,771,1285,3855,...}, and defines the XOR BINOMIAL transform of the powers of 2.
Rows begin:
1;
2, 3;
4, 6, 5;
8, 12, 10, 15;
16, 24, 20, 30, 17;
32, 48, 40, 60, 34, 51;
64, 96, 80, 120, 68, 102, 85;
128, 192, 160, 240, 136, 204, 170, 255;
256, 384, 320, 480, 272, 408, 340, 510, 257;
512, 768, 640, 960, 544, 816, 680, 1020, 514, 771;
1024, 1536, 1280, 1920, 1088, 1632, 1360, 2040, 1028, 1542, 1285;
2048, 3072, 2560, 3840, 2176, 3264, 2720, 4080, 2056, 3084, 2570, 3855;
...
From _Antti Karttunen_, Sep 19 2016: (Start)
Viewed as a square array, the top left corner looks like this:
1, 2, 4, 8, 16, 32, 64, 128
3, 6, 12, 24, 48, 96, 192, 384
5, 10, 20, 40, 80, 160, 320, 640
15, 30, 60, 120, 240, 480, 960, 1920
17, 34, 68, 136, 272, 544, 1088, 2176
51, 102, 204, 408, 816, 1632, 3264, 6528
85, 170, 340, 680, 1360, 2720, 5440, 10880
255, 510, 1020, 2040, 4080, 8160, 16320, 32640
257, 514, 1028, 2056, 4112, 8224, 16448, 32896
771, 1542, 3084, 6168, 12336, 24672, 49344, 98688
1285, 2570, 5140, 10280, 20560, 41120, 82240, 164480
3855, 7710, 15420, 30840, 61680, 123360, 246720, 493440
4369, 8738, 17476, 34952, 69904, 139808, 279616, 559232
...
(End)
The square array shown above can be viewed as a subtable of a multiplication table with particular relevance to the carryless multiplication defined by A048720, as the first column gives the A048720 powers of 3 (and the first row gives powers of 2, which are the same as in standard arithmetic). - _Peter Munn_, Jan 13 2020
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