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A088593
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a(0)=18; a(n+1) = largest odd factor of 3*a(n)+1; stop when a(n)=1.
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0
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18, 55, 83, 125, 47, 71, 107, 161, 121, 91, 137, 103, 155, 233, 175, 263, 395, 593, 445, 167, 251, 377, 283, 425, 319, 479, 719, 1079, 1619, 2429, 911, 1367, 2051, 3077, 577, 433, 325, 61, 23, 35, 53, 5, 1
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OFFSET
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0,1
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COMMENTS
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Similar to a Collatz sequence.
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LINKS
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Table of n, a(n) for n=0..42.
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FORMULA
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a(n+1) = A000265(3*a(n)+1). - Michel Marcus, Aug 23 2022
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EXAMPLE
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a(4)=47 because (a(3)*3+1)/2^3 = 47.
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PROG
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(PARI) f(n) = n >> valuation(n, 2); \\ A000265
lista(nn) = my(list=List(), x = 18, i=0); while (1, listput(list, x); x = f(3*x+1); i++; if (i>100, break)); Vec(list); \\ Michel Marcus, Aug 23 2022
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CROSSREFS
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Cf. A000265.
Sequence in context: A069973 A272138 A041630 * A033571 A041632 A086540
Adjacent sequences: A088590 A088591 A088592 * A088594 A088595 A088596
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KEYWORD
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easy,nonn,fini,full
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AUTHOR
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Mitch Cervinka (puritan(AT)planetkc.com), Nov 20 2003
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EXTENSIONS
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Edited by Don Reble, Nov 08 2005
Corrected by Doug Unger, Aug 26 2022
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STATUS
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approved
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