A037102 Trajectory of 3 under map n->9n+1 if n odd, n->n/2 if n even.

3, 28, 14, 7, 64, 32, 16, 8, 4, 2, 1, 10, 5, 46, 23, 208, 104, 52, 26, 13, 118, 59, 532, 266, 133, 1198, 599, 5392, 2696, 1348, 674, 337, 3034, 1517, 13654, 6827, 61444, 30722, 15361, 138250, 69125, 622126, 311063, 2799568, 1399784, 699892, 349946, 174973

Offset

0,1

Links

Table of n, a(n) for n=0..47.

Mathematica

NestList[If[EvenQ[#], #/2, 9#+1]&, 3, 50] (* Harvey P. Dale, Sep 06 2022 *)

Prog

(Python)
from itertools import accumulate
def f(n, _): return 9*n+1 if n%2 == 1 else n//2
def aupton(terms): return list(accumulate([3]*terms, f))
print(aupton(48)) # Michael S. Branicky, Mar 28 2021

Crossrefs

Sequence in context: A146072 A064234 A224579 * A042169 A041785 A157848

Adjacent sequences: A037099 A037100 A037101 * A037103 A037104 A037105

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved