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A228014
Numbers k whose Collatz sequence length is greater than k+1 (counting both the x/2 and the 3x+1 steps).
2
3, 6, 7, 9, 11, 14, 15, 18, 19, 27, 31, 41, 47, 54, 55, 62, 63, 71, 73, 82, 83, 91, 94, 95, 97, 108, 109, 110
OFFSET
1,1
EXAMPLE
a(1) is 3 because its Collatz sequence has eight steps: 3, 10, 5, 16, 8, 4, 2, 1.
MATHEMATICA
Select[Range[1000], Length[Collatz[#]] > #+1 &] (* T. D. Noe, Aug 20 2013 *)
CROSSREFS
Cf. A082984 (allows number of steps equal to n).
Sequence in context: A188974 A047558 A160217 * A188971 A176065 A333552
KEYWORD
nonn,more
AUTHOR
Gonzalo Ciruelos, Aug 02 2013
STATUS
approved