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 A327973 Bitwise XOR of two successive generations (centrally aligned) in the trajectory of rule 30 started from a lone 1 cell: a(n) = A110240(n) XOR 2*A110240(n-1). 10
 5, 23, 93, 335, 1493, 5351, 23853, 85951, 382405, 1369943, 6103965, 21996687, 97906325, 350709671, 1562619373, 5631262591, 25064000389, 89782414999, 400033474525, 1441615751887, 6416397448021, 22984338788455, 102408232210605, 369052763468095, 1642598765228869, 5883986891577303, 26216498605021469, 94477513773305103 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Antti Karttunen, Table of n, a(n) for n = 1..1024 Antti Karttunen, Terms a(1)-a(256) drawn as binary strings, with 1 bit = 3x3 pixels resolution Antti Karttunen, Terms a(1)-a(1024) drawn as binary strings, with 1 bit = 1 pixel resolution Index entries for sequences related to cellular automata FORMULA a(n) = A110240(n) XOR 2*A110240(n-1). PROG (PARI) A269160(n) = bitxor(n, bitor(2*n, 4*n)); \\ From A269160. A110240(n) = if(!n, 1, A269160(A110240(n-1))); A327973(n) = bitxor(A110240(n), 2*A110240(n-1)); \\ Use this one for writing b-files: A327973write(up_to) = { my(s=1, t, n=0); for(n=1, up_to, t = A269160(s); write("b327973.txt", n, " ", bitxor(2*s, t)); s = t); }; (Python) def A269160(n): return(n^((n<<1)|(n<<2))) def genA327973(): '''Yield successive terms of A327973.''' s = 1 while True: t = A269160(s) yield (t^(s<<1)) s = t CROSSREFS Cf. A110240, A269160, A327974 (gives the middle bit), A328107 (binary weight of terms). Cf. also A327971, A327972, A327976, A328103, A328104 for other such combinations. Sequence in context: A283224 A178834 A331720 * A255457 A146013 A028894 Adjacent sequences: A327970 A327971 A327972 * A327974 A327975 A327976 KEYWORD nonn AUTHOR Antti Karttunen, Oct 03 2019 STATUS approved

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Last modified December 3 05:03 EST 2023. Contains 367531 sequences. (Running on oeis4.)