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A134440
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a(0)=1; for n > 0, a(n) = a(n-1) + prime(n) if a(n-1) is odd, else a(n) = a(n-1)/2.
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1
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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
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OFFSET
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0,2
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COMMENTS
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LFSR with primes.
Is it true that Lim a(n)/prime(n) < square root(3)?
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REFERENCES
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T. Herlestam, On functions of linear shift register sequences. Springer Lecture notes in computer sciences, ISBN 978-3-540-16468-5.
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LINKS
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MAPLE
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option remember;
if n =0 then
1;
elif type(procname(n-1), 'odd') then
procname(n-1)+ithprime(n) ;
else
procname(n-1)/2 ;
end if;
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MATHEMATICA
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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 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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