Let
π
=
Π
2
{\displaystyle \pi =\Pi _{2}}
(length 16) ,
ϕ
=
Φ
3
{\displaystyle \phi =\Phi _{3}}
(length 16) and
ξ
=
Ξ
3
{\displaystyle \xi =\Xi _{3}}
(length 256) .
Let
I
k
=
{
i
∣
ξ
i
=
ϕ
k
}
{\displaystyle I_{k}~~=~~\{i\mid \xi _{i}=\phi _{k}\}}
be the set of places where
ξ
{\displaystyle \xi }
has the entry
ϕ
k
{\displaystyle \phi _{k}}
.
π
{\displaystyle \pi }
is the left column of the following matrix.
ϕ
{\displaystyle \phi }
is its top row, and also shown in the column to its right.
The matrix entries are the bitwise XORs of its left column and top row.
I
k
{\displaystyle I_{k}}
is row
k
{\displaystyle k}
as a set of numbers:
{
π
k
⊕
f
∣
f
∈
ϕ
}
{\displaystyle \{\pi _{k}\oplus f\mid f\in \phi \}}
Example: In which places is
ξ
{\displaystyle \xi }
equal to
ϕ
10
=
168
{\displaystyle \phi _{10}=168}
?
π
10
=
2
⟹
I
10
=
{
2
⊕
f
∣
f
∈
ϕ
}
=
{
2
,
28
,
.
.
.
,
226
,
252
}
{\displaystyle \pi _{10}=2~~~~\implies ~~~~I_{10}~~=~~\{2\oplus f\mid f\in \phi \}~~=~~\{2,28,...,226,252\}}
It can be easily seen, that the first and the last entry 168 in
ξ
{\displaystyle \xi }
is in places 2 and 252.
0
0
30
40
54
72
86
96
126
128
158
168
182
200
214
224
254
0
1
15
17
39
57
71
89
111
113
143
145
167
185
199
217
239
241
30
2
10
20
34
60
66
92
106
116
138
148
162
188
194
220
234
244
40
3
5
27
45
51
77
83
101
123
133
155
173
179
205
211
229
251
54
4
12
18
36
58
68
90
108
114
140
146
164
186
196
218
236
242
72
5
3
29
43
53
75
85
99
125
131
157
171
181
203
213
227
253
86
6
6
24
46
48
78
80
102
120
134
152
174
176
206
208
230
248
96
7
9
23
33
63
65
95
105
119
137
151
161
191
193
223
233
247
126
8
8
22
32
62
64
94
104
118
136
150
160
190
192
222
232
246
128
9
7
25
47
49
79
81
103
121
135
153
175
177
207
209
231
249
158
10
2
28
42
52
74
84
98
124
130
156
170
180
202
212
226
252
168
11
13
19
37
59
69
91
109
115
141
147
165
187
197
219
237
243
182
12
4
26
44
50
76
82
100
122
132
154
172
178
204
210
228
250
200
13
11
21
35
61
67
93
107
117
139
149
163
189
195
221
235
245
214
14
14
16
38
56
70
88
110
112
142
144
166
184
198
216
238
240
224
15
1
31
41
55
73
87
97
127
129
159
169
183
201
215
225
255
254
The lower 8×16 matrix corresponds to row 10. The one above contains the Zhegalkin indices, and has the same set of columns.
Nobles for comparison