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A075258 Larger terms of the pairs (a < b) in the sequence {a,b}-> {Max[{a,b}]-Min[{a,b}],k*Min[{a,b}]} with k=3 and the first pair {a=1,b=2}. See A075256. 3
2, 3, 3, 6, 5, 9, 7, 18, 17, 14, 27, 22, 45, 38, 63, 51, 138, 133, 118, 135, 219, 186, 471, 442, 355, 783, 689, 846, 1221, 1317, 2346, 1811, 4815, 4609, 3991, 5562, 6411, 10275, 8958, 21867, 20198, 15191, 45063, 44893, 44383, 42853, 38263, 41310 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Take any pair {a,b}. Each next pair is get by the rule {a,b} -> Sort[{Max[{a,b}]-Min[{a,b}],k*Min[{a,b}]]. Here k=3 and the first {a,b}={1,2}. For k = 2 there is a fixed point {a,b=2a}. For k > 2, are there any limits or cycles of the sequence {for some initial pair {a,b}?

LINKS

Hugo Pfoertner, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A075256(2*n).

MATHEMATICA

ss=Table[0, {j, 100}]; s=ss[[1]]={1, 2}; Do[ss[[i]]=Sort[{Max[s]-Min[s], 3*Min[s]}]; s=ss[[i]], {i, 2, 100}]; Table[Flatten[ss][[i]], {i, 2, 200, 2}]

PROG

(PARI) my(x=1, y=2); print1(y, ", "); for(n=2, 48, my(mx=max(x, y), mi=min(x, y)); x=min(mx-mi, 3*mi); y=max(mx-mi, 3*mi); print1(y, ", ")) \\ Hugo Pfoertner, Mar 21 2020

CROSSREFS

Cf. A075256, A075257.

Sequence in context: A333660 A187754 A347732 * A321745 A212629 A127779

Adjacent sequences: A075255 A075256 A075257 * A075259 A075260 A075261

KEYWORD

nonn

AUTHOR

Zak Seidov, Sep 10 2002

STATUS

approved

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Last modified February 7 02:40 EST 2023. Contains 360111 sequences. (Running on oeis4.)