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A327971
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Bitwise XOR of trajectories of rule 30 and its mirror image, rule 86, when both are started from a lone 1 cell: a(n) = A110240(n) XOR A265281(n).
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8
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0, 0, 10, 20, 130, 396, 2842, 4420, 38610, 124220, 684490, 1385044, 8891330, 26281036, 192525274, 269101060, 2454365330, 8588410876, 43860512138, 89059958420, 551714970626, 1663794165260, 12235920695450, 19683098342340, 164315052318034, 538162708968636, 2894532467106378, 6192136868790228, 37503903254935874, 114926395086966988, 814341599153559130
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,3
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COMMENTS
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Each term is a binary palindrome when its trailing zeros (in base 2) are omitted, that is, a term of A057890.
Compare the binary string illustrations drawn for the first 1024 terms of this sequence and for A327976, which has almost the same definition.
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LINKS
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FORMULA
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PROG
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(PARI)
A269161(n) = bitxor(4*n, bitor(2*n, n));
(PARI)
A030101(n) = if(n<1, 0, subst(Polrev(binary(n)), x, 2));
A327971write(up_to) = { my(s=1, n=0); for(n=0, up_to, write("b327971.txt", n, " ", bitxor(s, A030101(s))); s = A269160(s)); };
(Python)
def A269160(n): return(n^((n<<1)|(n<<2)))
def A269161(n): return((n<<2)^((n<<1)|n))
def genA327971():
'''Yield successive terms of A327971.'''
s1 = 1
s2 = 1
while True:
yield (s1^s2)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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