A213916 Sum of all odd numbers in Collatz (3x+1) trajectory of n.

1, 1, 9, 1, 6, 9, 54, 1, 63, 6, 47, 9, 19, 54, 132, 1, 36, 63, 95, 6, 22, 47, 117, 9, 120, 19, 20262, 54, 76, 132, 20194, 1, 153, 36, 94, 63, 91, 95, 450, 6, 20235, 22, 248, 47, 81, 117, 20163, 9, 140, 120, 204, 19, 59, 20262, 20426, 54, 305, 76, 411, 132, 178

Offset

1,3

Links

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

Formula

a(n) = A033493(n) - A213909(n).

Example

a(5)=6 since Collatz trajectory of 5 is 5,16,8,4,2,1.

Mathematica

Collatz[n_] := NestWhileList[If[EvenQ[#], #/2, 3 # + 1] &, n, # > 1 &]; Table[Total[Select[Collatz[n], OddQ]], {n, 100}] (* T. D. Noe, Mar 05 2013 *)

Crossrefs

Cf. A033493, A213909.

Sequence in context: A363876 A195712 A296473 * A297815 A021920 A367960

Adjacent sequences: A213913 A213914 A213915 * A213917 A213918 A213919

Keyword

nonn

Author

Jayanta Basu, Mar 05 2013

Status

approved