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A092539 Binary representation of a(n) equals first n+1 terms of A051023. 8
1, 3, 6, 13, 27, 55, 110, 220, 441, 883, 1766, 3532, 7064, 14129, 28258, 56517, 113035, 226070, 452140, 904281, 1808562, 3617124, 7234249, 14468499, 28936999, 57873998, 115747997, 231495994, 462991989, 925983979, 1851967959, 3703935918 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n+1) = 2*a(n) + d, where d = 0/1 with no obvious rule. The sequence is a digit representation of the central column of cellular automaton Rule 30, A051023. Primes in the sequence, A092540.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Rule 30.

FORMULA

a(n+1) = 2*a(n) + A051023(n+1). - Reinhard Zumkeller, Jun 08 2013

EXAMPLE

a(6) = 55_10 = 110111_2

MATHEMATICA

a(n_) := FromDigits[Take[A051023, n], 2]

PROG

(Haskell)

a092539 n = a092539_list !! n

a092539_list = scanl1 (\v d -> 2 * v + d) $ map toInteger a051023_list

-- Reinhard Zumkeller, Jun 08 2013

CROSSREFS

Cf. A051023, A092540.

Sequence in context: A079403 A065830 A055143 * A094386 A267604 A099036

Adjacent sequences:  A092536 A092537 A092538 * A092540 A092541 A092542

KEYWORD

easy,nonn

AUTHOR

Zak Seidov, Feb 27 2004

EXTENSIONS

Offset corrected and definition adjusted by Reinhard Zumkeller, Jun 08 2013

STATUS

approved

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Last modified July 23 00:43 EDT 2019. Contains 325228 sequences. (Running on oeis4.)