A213917 Difference between sum of all even and the sum of all odd numbers in Collatz (3x+1) trajectory of n.

-1, 1, 31, 5, 24, 37, 180, 13, 213, 34, 165, 49, 81, 194, 430, 29, 142, 231, 329, 54, 104, 187, 399, 73, 418, 107, 60916, 222, 290, 460, 60716, 61, 535, 176, 352, 267, 353, 367, 1444, 94, 60861, 146, 842, 231, 335, 445, 60653, 121, 526, 468, 722, 159, 281

Offset: 1

Author

Jayanta Basu, Mar 05 2013

Keywords

• sign

Links

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

Crossrefs

Cf. A213909, A213916.

Programs

Mathematica

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

Formula

a(n) = A213909(n) - A213916(n).