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--- chess:programming:de_bruijn_sequence [2021/10/30 14:01] – peter
+++ chess:programming:de_bruijn_sequence [2021/10/30 16:52] (current) – peter
@@ Line 55: / Line 55: @@
 **NOTE:** The last 3 wraps around to the start to get the 4th digit.
 </WRAP>
+----
+===== de Bruijn values =====
+^n^de Bruijn^
+|1|01|
+|2|1100|
+|3|00010111|
+|3|01110100|
+|4|0000100110101111|
+|4|1111011001010000|
+|5|11010100111011000101111100100000|
+|6|0000001000011000101001111010001110010010110111011001101010111111|
 ----
@@ Line 67: / Line 81: @@
 [[Chess:Programming:de Bruijn Sequence:Using a De Bruijn Sequence|Using a De Bruijn Sequence]]
+[[Chess:Programming:de Bruijn Sequence:8-bit Example|8-bit Example]]
 ----
+TODO
+<code>
+Why does the standard numbering equation for de Bruijn sequences give differing results for dB(16,4) and dB(2,16), when both are 16 bits?
+De Bruijn sequences are numbered by the equation
+dB(k,n) = ((k!)^(k^(n-1)))/(k^n).
+When we have dB(2,16), the computed value is of the order 2.1598E+9859 .
+For dB(16,4), the computed value is of the order 2.7629E+54556.
+Yet, both sequences are represented within just 64K bytes of memory.
+Only one of these computations can be correct.
+</code>
+----
 ===== References =====