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A226667
Conjectured record-breaking values, for ascending positive integers k, of the maximal element of the primitive cycles of positive integers under iteration by the Collatz-like 3x+k function.
4
1, 3397, 2277097, 106035623, 128946539, 153247321, 885327131, 6372904817, 52894692341, 95712964765, 301829916841, 1846456176103, 2697688935023, 10281192195005, 10556691785131, 13239192635131
OFFSET
1,2
COMMENTS
A cycle is called primitive if its elements are not a common multiple of the elements of another cycle.
The 3x+k function T_k is defined by T_k(x) = x/2 if x is even, (3x+k)/2 if x is odd.
For primitive cycles, GCD(k,6)=1.
CROSSREFS
k = A226668(n). The smallest integer in the T_k cycle associated with a(n) is A226669(n).
Sequence in context: A185573 A185926 A221009 * A206507 A133532 A224744
KEYWORD
nonn
AUTHOR
Geoffrey H. Morley, Jun 15 2013
STATUS
approved