A161022 Collatz (or 3x+1) trajectory starting at 10087.

10087, 30262, 15131, 45394, 22697, 68092, 34046, 17023, 51070, 25535, 76606, 38303, 114910, 57455, 172366, 86183, 258550, 129275, 387826, 193913, 581740, 290870, 145435, 436306, 218153, 654460, 327230, 163615, 490846, 245423, 736270

Offset: 0

Author

Reinhard Zumkeller, Jun 03 2009

Keywords

• nonn
• easy

Comments

10087 = A060412(6); a(A006577(10087)) = a(223) = 1;

a(n)=A161021(n-53)=A161023(n+100) for n with 208<=n<=228.

At step 221 becomes periodic: 4 2 1 4 2 1 4 2 1 ... - N. J. A. Sloane, Jul 27 2019

Links

• R. Zumkeller, Table of n, a(n) for n = 0..223
• Index entries for sequences related to 3x+1 (or Collatz) problem
• Index entries for linear recurrences with constant coefficients, signature (0,0,1).

Crossrefs

A008884.

Programs

Mathematica

NestList[If[EvenQ[#],#/2,3#+1]&,10087,30] (* Harvey P. Dale, Jul 25 2023 *)

Extensions

Edited by N. J. A. Sloane, Jul 27 2019