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A213330
Minimum deviation from n in Collatz trajectory of n.
1
0, 1, 1, 2, 1, 1, 1, 4, 1, 2, 1, 2, 3, 1, 1, 8, 1, 1, 1, 4, 5, 2, 3, 8, 1, 6, 4, 2, 3, 5, 4, 16, 1, 6, 5, 2, 3, 2, 1, 20, 1, 10, 3, 4, 5, 6, 1, 24, 3, 2, 1, 12, 13, 1, 2, 4, 1, 6, 1, 7, 8, 1, 2, 32, 9, 8, 9, 16, 17, 10, 1, 20, 2, 18, 10, 12, 11, 2, 3, 40, 1, 2
OFFSET
1,4
COMMENTS
Assuming Collatz trajectory ends with 1 and also a(1)=0.
EXAMPLE
a(4)=2 because the number closest to 4 in Collatz trajectory of 4 is 2.
MATHEMATICA
Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; Join[{0}, Table[Min[Rest[Abs[Collatz[n] - n]]], {n, 2, 100}]]
CROSSREFS
Cf. A070165, A355239 (indices of 1's).
Sequence in context: A174555 A157113 A214712 * A139320 A174204 A118106
KEYWORD
nonn
AUTHOR
Jayanta Basu, Mar 03 2013
STATUS
approved