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A087251
Distinct largest-peak-values in 3x+1 trajectory arranged by their first appearance as initial value increases. A025586 without repetitions while keeping order.
4
1, 2, 16, 4, 52, 8, 40, 160, 88, 20, 64, 24, 9232, 32, 100, 112, 304, 196, 136, 48, 148, 232, 56, 184, 68, 208, 72, 340, 808, 80, 244, 84, 256, 592, 280, 96, 448, 104, 520, 116, 352, 628, 4372, 128, 132, 400, 916, 424, 144, 1024, 152, 472, 736, 168, 176, 532, 180
OFFSET
1,2
EXAMPLE
peak=160 appears in trajectory started with n=15 and
before peaks = 1,2,16,4,52,8,40 appear at n=1,..,14
initial values: 160=a(8), the 8th new peak-value.
CROSSREFS
Cf. A025586.
Sequence in context: A232503 A348007 A025586 * A336833 A211367 A351585
KEYWORD
nonn
AUTHOR
Labos Elemer, Sep 08 2003
STATUS
approved