A256258
Triangle read by rows in which the row lengths are the terms of A011782 and row n lists the terms of A016969 except for the right border which gives the positive terms of A000225.
Original entry on oeis.org
1, 3, 5, 7, 5, 11, 17, 15, 5, 11, 17, 23, 29, 35, 41, 31, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89, 63, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89, 95, 101, 107, 113, 119, 125, 131, 137, 143, 149, 155, 161, 167, 173, 179, 185, 127, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89, 95, 101, 107, 113, 119, 125, 131, 137
Offset: 1
Written as an irregular triangle in which the row lengths are the terms of A011782, the sequence begins:
1;
3;
5,7;
5,11,17,15;
5,11,17,23,29,35,41,31;
5,11,17,23,29,35,41,47,53,59,65,71,77,83,89,63;
5,11,17,23,29,35,41,47,53,59,65,71,77,83,89,95,101,107,113,119,125,131,137,143,149,155,161,167,173,179,185,127;
...
Illustration of initial terms in the fourth quadrant of the square grid:
------------------------------------------------------------------------
n a(n) Compact diagram
------------------------------------------------------------------------
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
1 1 |_| | | |_ _ | |_ _ _ _ _ _ | |
2 3 |_ _| | |_ | | |_ _ _ _ _ | | |
3 5 |_ _ _| | | | | |_ _ _ _ | | | |
4 7 |_ _ _ _| | | | |_ _ _ | | | | |
5 5 | | |_ _ _| | | |_ _ | | | | | |
6 11 | |_ _ _ _ _| | |_ | | | | | | |
7 17 |_ _ _ _ _ _ _| | | | | | | | | |
8 15 |_ _ _ _ _ _ _ _| | | | | | | | |
9 5 | | | | | | |_ _ _| | | | | | | |
10 11 | | | | | |_ _ _ _ _| | | | | | |
11 17 | | | | |_ _ _ _ _ _ _| | | | | |
12 23 | | | |_ _ _ _ _ _ _ _ _| | | | |
13 29 | | |_ _ _ _ _ _ _ _ _ _ _| | | |
14 35 | |_ _ _ _ _ _ _ _ _ _ _ _ _| | |
15 41 |_ _ _ _ _ _ _ _ _ _ _ _ _ _ _| |
16 31 |_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _|
.
a(n) is also the number of cells in the n-th region of the diagram.
It appears that A241717 can be represented by a similar diagram.
Cf.
A000225,
A000302,
A002001,
A011782,
A016969,
A141548,
A241717,
A256260,
A256261,
A256263,
A256264.
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Nest[Join[#, Range[Length[#] - 1]*6 - 1, {2 #[[-1]] + 1}] &, {1}, 7] (* Ivan Neretin, Feb 14 2017 *)
A236305
The number of P-positions in the game of Nim with up to 3 piles, allowing for piles of zero, such that the number of objects in each pile does not exceed n.
Original entry on oeis.org
1, 4, 7, 16, 19, 28, 43, 64, 67, 76, 91, 112, 139, 172, 211, 256, 259, 268, 283, 304, 331, 364, 403, 448, 499, 556, 619, 688, 763, 844, 931, 1024, 1027, 1036, 1051, 1072, 1099, 1132, 1171, 1216, 1267, 1324, 1387, 1456, 1531, 1612, 1699
Offset: 0
If the largest number is 1, then there should be an even number of piles of size 1. Thus, a(1)=4.
- Michael De Vlieger, Table of n, a(n) for n = 0..1024
- Hsien-Kuei Hwang, Svante Janson, and Tsung-Hsi Tsai, Identities and periodic oscillations of divide-and-conquer recurrences splitting at half, arXiv:2210.10968 [cs.DS], 2022, p. 37.
- T. Khovanova and J. Xiong, Nim Fractals, arXiv:1405.594291 [math.CO] (2014), p. 7 and J. Int. Seq. 17 (2014) # 14.7.8.
-
Table[Length[Select[Flatten[Table[{n, k, BitXor[n, k]}, {n, 0, a}, {k, 0, a}], 1], #[[3]] <= a &]], {a, 0, 100}]
A241718
The number of P-positions in the game of Nim with up to 4 piles, allowing for piles of zero, such that the number of objects in the largest pile is n.
Original entry on oeis.org
1, 7, 13, 43, 25, 79, 133, 211, 49, 151, 253, 379, 457, 607, 757, 931, 97, 295, 493, 715, 889, 1135, 1381, 1651, 1681, 1975, 2269, 2587, 2857, 3199, 3541, 3907, 193, 583, 973, 1387, 1753, 2191, 2629, 3091, 3313, 3799, 4285, 4795, 5257, 5791, 6325
Offset: 0
If the largest pile is 2, then there are 6 positions that are permutations of (0,0,2,2) plus 6 positions that are permutations of (1,1,2,2) and one position (2,2,2,2). Therefore, a(2)=13.
-
Table[Length[Select[Flatten[Table[{n, k, j, BitXor[n, k, j]}, {n, 0, a}, {k, 0, a}, {j, 0, a}], 2], Max[#] == a &]], {a, 0, 50}]
A241731
The number of P-positions in the game of Nim with up to 5 piles, allowing for piles of zero, such that the number of objects in the largest pile is n.
Original entry on oeis.org
1, 15, 45, 195, 165, 555, 1125, 1995, 645, 1995, 3525, 5355, 7605, 10395, 13845, 18075, 2565, 7755, 13125, 18795, 24885, 31515, 38805, 46875, 55845, 65835, 76965, 89355, 103125, 118395, 135285, 153915, 10245, 30795, 51525, 72555, 94005, 115995
Offset: 0
If the largest pile is 1, then there are 10 positions that are permutations of (0,0,0,1,1) plus 5 positions that are permutations of (0,1,1,1,1). Therefore, a(1)=15.
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Table[Length[Select[Flatten[Table[{n, k, j, i, BitXor[n, k, j, i]}, {n, 0, a}, {k, 0, a}, {j, 0, a}, {i, 0, a}], 3], Max[#] == a &]], {a, 0, 50}]
Original entry on oeis.org
0, 4, 12, 12, 36, 12, 36, 60, 84, 12, 36, 60, 84, 108, 132, 156, 180, 12, 36, 60, 84, 108, 132, 156, 180, 204, 228, 252, 276, 300, 324, 348, 372, 12, 36, 60, 84, 108, 132, 156, 180, 204, 228, 252, 276, 300, 324, 348, 372, 396, 420, 444, 468, 492, 516, 540, 564, 588, 612, 636, 660, 684, 708, 732, 756, 12, 36, 60, 84, 108
Offset: 0
With the positive terms written as an irregular triangle in which the row lengths are the terms of A011782 the sequence begins:
4;
12;
12, 36;
12, 36, 60, 84;
12, 36, 60, 84, 108, 132, 156, 180;
12, 36, 60, 84, 108, 132, 156, 180, 204, 228, 252, 276, 300, 324, 348, 372;
...
A256255
Triangle read by rows: T(n,k) = 6*k + 1, n>=0, 0<=k<=(2^n-1).
Original entry on oeis.org
1, 1, 7, 1, 7, 13, 19, 1, 7, 13, 19, 25, 31, 37, 43, 1, 7, 13, 19, 25, 31, 37, 43, 49, 55, 61, 67, 73, 79, 85, 91, 1, 7, 13, 19, 25, 31, 37, 43, 49, 55, 61, 67, 73, 79, 85, 91, 97, 103, 109, 115, 121, 127, 133, 139, 145, 151, 157, 163, 169, 175, 181, 187, 1, 7, 13, 19, 25, 31, 37, 43, 49, 55, 61, 67, 73, 79, 85, 91, 97, 103
Offset: 0
Triangle begins:
1;
1,7;
1,7,13,19;
1,7,13,19,25,31,37,43;
1,7,13,19,25,31,37,43,49,55,61,67,73,79,85,91;
...
Illustration of initial terms in the fourth quadrant of the square grid:
------------------------------------------------------------------------
n a(n) Compact diagram
------------------------------------------------------------------------
. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
0 1 |_|_ |_ _ _ |_ _ _ _ _ _ _ |
1 1 | |_| |_ _ | |_ _ _ _ _ _ | |
2 7 |_ _ _|_ | | |_ _ _ _ _ | | |
3 1 | | | |_| | | |_ _ _ _ | | | |
4 7 | | |_ _ _| | |_ _ _ | | | | |
5 13 | |_ _ _ _ _| |_ _ | | | | | |
6 19 |_ _ _ _ _ _ _|_ | | | | | | |
7 1 | | | | | | | |_| | | | | | | |
8 7 | | | | | | |_ _ _| | | | | | |
9 13 | | | | | |_ _ _ _ _| | | | | |
10 19 | | | | |_ _ _ _ _ _ _| | | | |
11 25 | | | |_ _ _ _ _ _ _ _ _| | | |
12 31 | | |_ _ _ _ _ _ _ _ _ _ _| | |
13 37 | |_ _ _ _ _ _ _ _ _ _ _ _ _| |
14 43 |_ _ _ _ _ _ _ _ _ _ _ _ _ _ _|
.
a(n) is also the number of cells in the n-th region of the diagram.
For other diagrams of the same family see A241717 and A256258.
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With[{rows=7},Array[Range[1,6*2^#,6]&,rows,0]] (* Paolo Xausa, Sep 26 2023 *)
Showing 1-6 of 6 results.
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