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A375266
Irregular triangle read by rows in which row n lists the iterates of the A375265 map from n to 1.
5
1, 2, 1, 3, 1, 4, 2, 1, 5, 16, 8, 4, 2, 1, 6, 2, 1, 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 8, 4, 2, 1, 9, 3, 1, 10, 5, 16, 8, 4, 2, 1, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 12, 4, 2, 1, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1
OFFSET
1,2
COMMENTS
By definition the trajectory ends when 1 is reached, so row 1 does not contain the cycle 1 -> 4 -> 2 -> 1.
See A375265 for links.
LINKS
EXAMPLE
Triangle begins:
1;
2, 1;
3, 1;
4, 2, 1;
5, 16, 8, 4, 2, 1;
6, 2, 1;
7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1;
8, 4, 2, 1;
9, 3, 1;
10, 5, 16, 8, 4, 2, 1;
...
MATHEMATICA
A375265[n_] := Which[Divisible[n, 3], n/3, Divisible[n, 2], n/2, True, 3*n + 1];
Array[NestWhileList[A375265, #, # > 1 &] &, 15]
CROSSREFS
Cf. A375265, A375267 (# of iterations), A375268 (row sums), A375280 (row maxs).
Sequence in context: A347285 A132460 A238800 * A067734 A303758 A161904
KEYWORD
nonn,tabf,easy
AUTHOR
Paolo Xausa, Aug 08 2024
STATUS
approved