A063043 Collatz-2 (A063041) trajectory starting at 17.

17, 222, 111, 37, 1148, 574, 287, 41, 1518, 759, 253, 23, 438, 219, 73, 5184, 2592, 1296, 648, 324, 162, 81, 27, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36, 18, 9, 3, 7, 36

Offset

0,1

Comments

a(23) = a(28) = 9 and a(i) = a(j) <==> i = j for i, j < 28; same cycle values as A063042 but the conjecture that this is the only cycle for all starting values is not true: see A063044

Links

Table of n, a(n) for n=0..66.

Formula

a(0) = 17 and a(n) = A063041(a(n-1)) for n > 0

Mathematica

NestList[If[PrimeQ[#], #*Prime[PrimePi[#]-1]+1, #/Min@@First/@FactorInteger[#]]&, 17, 30] (* Jayanta Basu, May 27 2013 *)

Crossrefs

Cf. A063041, A063042, A063044.

Sequence in context: A016238 A016181 A285233 * A016174 A016281 A160398

Adjacent sequences: A063040 A063041 A063042 * A063044 A063045 A063046

Keyword

easy,nonn

Author

Reinhard Zumkeller, Jul 07 2001

Extensions

More terms from Sean A. Irvine, Apr 16 2023

Status

approved