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A127834
Numbers whose 8-bit binary representation, when rotated by up to one bit, contains every 3-bit binary representation for the numbers 0 through 7.
0
23, 29, 46, 58, 71, 92, 113, 116, 139, 142, 163, 184, 197, 209, 226, 232
OFFSET
1,1
COMMENTS
The binary representations of these numbers are equivalent under rotation / complement.
When this binary representation, with two bits from one end concatenated to the other, is given as input to an elementary cellular automaton, the first line of output will uniquely identify the rule of the automaton.
LINKS
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
EXAMPLE
23 has the 8-bit representation 00010111.
Concatenate the last two digits onto the beginning to get 1100010111.
We read off the 3-bit substrings:
110
100
000
001
010
101
011
111
PROG
(Sage)
i = 0
while i < 256:
bin = i.binary()
bin = bin[ -2:] + "0"*(8-len(bin)) + bin
subs = []
for j in range(8):
k = bin[j:j+3]
if k not in subs:
subs.append(k)
else: break
if len(subs) == 8: print(i)
i += 1
CROSSREFS
Sequence in context: A095077 A106989 A106988 * A108111 A085713 A102904
KEYWORD
fini,full,nonn
AUTHOR
Tomas Boothby, Feb 01 2007
STATUS
approved