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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.

A351699 T(n,k) is the number of non-congruent maximal subsets of a grid of n X k lattice points (k <= n), such that no two points are at the same distance, and the points do not fit into a smaller grid. The size of the subsets is given by A351700. T(n,k) and A351700 are triangles read by rows.

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%I A351699 #25 Jul 14 2022 16:41:20
%S A351699 1,1,1,1,2,1,1,1,5,10,1,5,28,7,21,2,19,8,104,330,2,1,4,70,15,110,574,
%T A351699 1,3,30,272,205,4,71,563,1991,4,68,50,1001,113,1130,4,76,383,9,8,362,
%U A351699 35,1150,23,363,3975,7,38,8,18,1082,415,2,638,7503,23,515,5802,2,2,150,62,4238,120,1,55,1776,17277,26,481,2388
%N A351699 T(n,k) is the number of non-congruent maximal subsets of a grid of n X k lattice points (k <= n), such that no two points are at the same distance, and the points do not fit into a smaller grid. The size of the subsets is given by A351700. T(n,k) and A351700 are triangles read by rows.
%C A351699 Configurations of points differing by any combination of rotation and reflection are counted only once.
%H A351699 Hugo Pfoertner, <a href="/A351699/b351699.txt">Table of n, a(n) for n = 1..91</a>, rows 1..13 of triangle, flattened
%e A351699 The triangle begins:
%e A351699   #
%e A351699   # 1:  1                   Counting grids n X k.
%e A351699       ( 1 )                 Two lines per side length n:
%e A351699   # 2:  2  2                1. for other side k = 1, 2, ...
%e A351699       ( 1  1 )                 maximal number of points
%e A351699   # 3:  2  3    3           2. number of configurations
%e A351699       ( 1  2    1 )
%e A351699   # 4:  3  4    4    4      Example: 28 figures with
%e A351699       ( 1  1    5   10 )             4 points on 5 X 3
%e A351699   # 5:  3  4    4    5    5
%e A351699       ( 1  5   28    7   21 )
%e A351699   # 6:  3  4    5    5    5    6
%e A351699       ( 2 19    8  104  330    2 )
%e A351699   # 7:  4  5    5    6    6    6    7
%e A351699       ( 1  4   70   15  110  574    1 )
%e A351699   # 8:  4  5    5    6    7    7    7     7
%e A351699       ( 3 30  272  205    4   71  563  1991 )
%e A351699   # 9:  4  5    6    6    7    7    8    8   8
%e A351699       ( 4 68   50 1001  113 1130    4   76 383 )
%e A351699   #10:  4  6    6    7    7    8    8    8   9    9
%e A351699       ( 9  8  362   35 1150   23  363 3975   7   38 )
%e A351699   #11:  4  6    6    7    8    8    8    9   9    9 10
%e A351699       ( 8 18 1082  415    2  638 7503   23 515 5802  2 )
%e A351699   #
%e A351699   #   Grid n X k configurations with
%e A351699   #       distinct distances
%e A351699   .
%e A351699   .
%e A351699   All T(6,3) = 8 configurations
%e A351699            0  1  2  3  4  5                    0  1  2  3  4  5
%e A351699          -------------------                 -------------------
%e A351699       2 |  .  X  X  .  X  .               2 |  .  .  .  .  X  .
%e A351699       1 |  .  .  .  .  .  X               1 |  .  .  .  .  .  X
%e A351699       0 |  X  .  .  .  .  .               0 |  X  .  X  .  .  X
%e A351699       y /-------------------              y /-------------------
%e A351699         x  0  1  2  3  4  5                 x  0  1  2  3  4  5
%e A351699     {1,2,4,5,8,9,10,17,20,26}  dist^2   {1,2,4,5,8,9,10,20,25,26}
%e A351699            0  1  2  3  4  5                    0  1  2  3  4  5
%e A351699          -------------------                 -------------------
%e A351699       2 |  .  .  X  .  X  .               2 |  .  X  .  X  .  .
%e A351699       1 |  .  .  .  .  .  X               1 |  X  .  .  .  .  .
%e A351699       0 |  X  X  .  .  .  .               0 |  X  .  .  .  .  X
%e A351699       y /-------------------              y /-------------------
%e A351699         x  0  1  2  3  4  5                 x  0  1  2  3  4  5
%e A351699     {1,2,4,5,8,10,13,17,20,26}  dist^2  {1,2,4,5,8,10,13,20,25,26}
%e A351699            0  1  2  3  4  5                    0  1  2  3  4  5
%e A351699          -------------------                 -------------------
%e A351699       2 |  .  .  .  .  X  .               2 |  .  .  X  .  X  .
%e A351699       1 |  X  .  .  .  .  X               1 |  X  .  .  .  .  X
%e A351699       0 |  X  .  X  .  .  .               0 |  X  .  .  .  .  .
%e A351699       y /-------------------              y /-------------------
%e A351699         x  0  1  2  3  4  5                 x  0  1  2  3  4  5
%e A351699     {1,2,4,5,8,10,17,20,25,26}  dist^2  {1,2,4,5,8,10,17,20,25,26}
%e A351699            0  1  2  3  4  5                    0  1  2  3  4  5
%e A351699          -------------------                 -------------------
%e A351699       2 |  .  .  X  .  .  X               2 |  X  .  .  .  .  X
%e A351699       1 |  .  .  .  .  .  .               1 |  .  .  .  .  .  .
%e A351699       0 |  X  X  .  .  .  X               0 |  X  .  .  X  X  .
%e A351699       y /-------------------              y /-------------------
%e A351699         x  0  1  2  3  4  5                 x  0  1  2  3  4  5
%e A351699     {1,4,5,8,9,13,16,20,25,29}  dist^2  {1,4,5,8,9,13,16,20,25,29}
%e A351699   .
%Y A351699 Cf. A193838, A193839, A271490, A325677, A335232, A351700, A351701.
%K A351699 nonn,tabl,hard
%O A351699 1,5
%A A351699 _Rainer Rosenthal_ and _Hugo Pfoertner_, Apr 09 2022
%E A351699 Completed row 8 and new rows 9-12 from _Hugo Pfoertner_, Jul 12 2022