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A075479
Number of iteration that first becomes smaller than the initial value if Collatz-function (A006370) is iterated, starting with numbers of form 64n+31. Corresponds to selection of every 16th term from A074474.
1
92, 14, 35, 51, 17, 14, 25, 27, 22, 14, 64, 17, 22, 14, 61, 43, 131, 14, 27, 22, 17, 14, 33, 35, 22, 14, 53, 17, 20, 14, 43, 22, 22, 14, 45, 22, 17, 14, 35, 43, 20, 14, 25, 17, 25, 14, 20, 22, 27, 14, 38, 20, 17, 14, 27, 22, 30, 14, 25, 17, 33, 14, 40, 20, 69, 14, 115, 27, 17
OFFSET
0,1
COMMENTS
Remark that initial values of form 64m+r, if r={3,11,19,27,35,43,51,55} provide first-sink-lengths {7,9,7,9,7,9,7,9} respectively; e.g. {64k+19,192k+58,96k+29,288k+88,144k+44,72k+22,36k+11} submerge first below initial value at the 7th term,36k+11<64k+19.
FORMULA
a(n)=A075473[64n+31], n=0, ..., 256
EXAMPLE
n=1: 64n+31=95,list={95,286,143,430,215,646,323,970, 485,1456,728,364,182,91,274,...}, i.e. the 14th term=91 is the first that <95, the initial value, so a(1)=14.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Sep 23 2002
STATUS
approved