A327973 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

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).

14

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