OFFSET
1,3
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-1).
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, 1, 199, 2}]
PROG
(PARI) my(x=1, y=2); print1(x, ", "); for(n=2, 53, my(mx=max(x, y), mi=min(x, y)); x=min(mx-mi, 3*mi); y=max(mx-mi, 3*mi); print1(x, ", ")) \\ Hugo Pfoertner, Mar 21 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
Zak Seidov, Sep 10 2002
STATUS
approved