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A134440 a(0)=1; for n > 0, a(n) = a(n-1)+ p(n) if a(n-1) is odd, else a(n) = a(n-1)/2. Here p(n) is the n-th prime number. 1
1, 3, 6, 3, 10, 5, 18, 9, 28, 14, 7, 38, 19, 60, 30, 15, 68, 34, 17, 84, 42, 21, 100, 50, 25, 122, 61, 164, 82, 41, 154, 77, 208, 104, 52, 26, 13, 170, 85, 252, 126, 63, 244, 122, 61, 258, 129, 340, 170, 85, 314, 157, 396, 198, 99, 356, 178, 89, 360, 180, 90, 45 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

LFSR with primes.

Is it true that Lim a(n)/p(n) < square root(3)?

REFERENCES

T. Herlestam,On functions of linear shift register sequences. Springer Lecture notes in computer sciences, ISBN 978-3-540-16468-5.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Schmidt, Georg; and Sidorenko, Vladimir R., Linear Shift-Register Synthesis for Multiple Sequences of Varying Length

Boaz Tsaban and Uzi Vishne, Efficient linear feedback shift registers with maximal period

MATHEMATICA

nxt[{n_, a_}]:={n+1, If[OddQ[a], a+Prime[n+1], a/2]}; Transpose[ NestList[ nxt, {0, 1}, 70]][[2]] (* Harvey P. Dale, Jan 12 2016 *)

CROSSREFS

Cf. A000040, A135287.

Sequence in context: A055373 A263333 A328371 * A129529 A298263 A128503

Adjacent sequences:  A134437 A134438 A134439 * A134441 A134442 A134443

KEYWORD

nonn

AUTHOR

Ctibor O. Zizka, Jan 18 2008

STATUS

approved

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Last modified January 22 06:03 EST 2021. Contains 340360 sequences. (Running on oeis4.)