A213330 Minimum deviation from n in Collatz trajectory of n.

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.

Links

T. D. Noe, Table of n, a(n) for n = 1..10000

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

Adjacent sequences: A213327 A213328 A213329 * A213331 A213332 A213333

Keyword

nonn

Author

Jayanta Basu, Mar 03 2013

Status

approved