A375911 - OEIS

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A375911

Largest value in the trajectory of 2*n - 1 in the Farkas map (A349407).

1, 3, 5, 17, 9, 17, 17, 15, 17, 29, 21, 53, 25, 27, 29, 161, 33, 53, 37, 39, 41, 65, 45, 161, 49, 51, 53, 125, 57, 89, 161, 63, 65, 101, 69, 161, 73, 75, 77, 269, 81, 125, 85, 87, 89, 137, 161, 485, 97, 99, 101, 233, 105, 161, 125, 111, 113, 173, 117, 269, 161

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Paolo Xausa, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = max{A350279(n,k) for 1 <= k <= A375909(n) + 1}.

EXAMPLE

a(10) = 29 because 29 is the largest value in the trajectory 19 -> 29 -> 15 -> 5 -> 3 -> 1.

MATHEMATICA

FarkasStep[x_] := Which[Divisible[x, 3], x/3, Mod[x, 4] == 3, (3*x + 1)/2, True, (x + 1)/2];

Array[Max[FixedPointList[FarkasStep, 2*# - 1]] &, 100]