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A353957
a(n) = (85*4^n - 1)/3.
0
113, 453, 1813, 7253, 29013, 116053, 464213, 1856853, 7427413, 29709653, 118838613, 475354453, 1901417813, 7605671253, 30422685013, 121690740053, 486762960213, 1947051840853, 7788207363413, 31152829453653, 124611317814613, 498445271258453, 1993781085033813
OFFSET
1,1
COMMENTS
When any term in the sequence is iterated using the Collatz function, its trajectory's only odd number before reaching 1 will be 85.
Also, each term would have 2n+10 steps as its stopping time (A006577).
EXAMPLE
When n=5, a(5) = 29013 and when iterated using the Collatz function will have the following trajectory: 87040,43520,21760,10880,5440,2720,1360,680,340,170,85,256,128,64,32,16,8,4,2,1
MATHEMATICA
(85*4^Range[25] - 1)/3 (* Wesley Ivan Hurt, Nov 10 2023 *)
PROG
(PARI) a(n) = 85*4^n\3 \\ Charles R Greathouse IV, Sep 09 2022
CROSSREFS
Subsequence of A198584.
Cf. A006577.
Sequence in context: A111013 A300537 A342816 * A142850 A203722 A118506
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Simpler definition and more terms from Jon E. Schoenfield, Sep 09 2022
STATUS
approved