A119559 Inverse Euler transform of A119268.
0, 1, 0, 1, 2, 3, 6, 12, 24, 49, 108, 239, 554, 1311, 3200
Offset: 0
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
Table starts: 1, 1, 1, 1, 1 1, 1, 1, 1, 1 1, 2, 2, 2, 2 1, 3, 4, 4, 4 1, 4, 6, 7, 7 1, 6, 11, 13, 14
Table starts: 1, 1, 1, 1, 1, 1, ... 1, 1, 2, 3, 4, 6, ... 1, 1, 2, 4, 6, 11, ... 1, 1, 2, 4, 7, 13, ... 1, 1, 2, 4, 7, 14, ... ...
The ordering of "conjugacy classes" of partitions begins: (1), (2), (3), (2+1), (4), (3+1), (2+2), ((2+1)+(1)), (5), (4+1), (3+2), (3+1+1), ((3+1)+(1)), ((2+2)+(1)), (((2+1)+(1))+((1))), ... The 14th partition, ((2+2)+(1)), is associated to the Young diagram with cubes centered at p_1=(0,0,0), p_2=(1,0,0), p_3=(0,1,0), p_4=(1,1,0), and p_5=(0,0,1). The possible ways to fill the cubes centered on these points so that the numbers are increasing in all directions are; (For each i=1:5, the i-th integer in a sequence below is placed on p_i.) 1-2-3-4-5 1-3-2-4-5 1-2-3-5-4 1-3-2-5-4 1-2-4-5-3 1-4-2-5-3 1-3-4-5-2 1-4-3-5-2 Hence the 14th term is 8. The 48th partition, ((2+2)+(2+2)), can be represented as a cube divided into octants. The integers 1 and 8 must lie in opposite octants. Of the three octants adjacent to the one which contains 1, one must contain 2 and one must contain 3. This gives 6 possibilities. For each of these possibilities there are 4 numbers (4, 5, 6, and 7) to choose from for the number placed in the remaining cube in the plane that contains 1, 2, and 3. Regardless of this choice, there are 2 ways to fill in the remaining three octants. Thus there are 6*4*2=48 ways to fill the octants all together--that is, the 48th multidimensional Young number is 48. Example of recursion: The partition: p|--6=((3+2)+(1)) covers the following partitions of 5: q_1|--5=(3+2) q_2|--5=((3+1)+(1)) q_3|--5=((2+2)+(1)) Thus Y(p)=Y(q_1)+Y(q_2)+Y(q_3)=5+12+8=25
% See MATLAB function in Links.
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