A075478 Number of iteration that first becomes smaller than the initial value if Collatz-function (A006370) is iterated, starting with numbers of form 64n+27. Corresponds to selection of every 16th term from A074474.

97, 74, 66, 14, 40, 17, 25, 14, 22, 27, 40, 14, 45, 27, 17, 14, 40, 38, 27, 14, 56, 17, 20, 14, 22, 27, 30, 14, 100, 30, 17, 14, 22, 33, 20, 14, 22, 17, 30, 14, 20, 30, 53, 14, 38, 20, 17, 14, 51, 25, 66, 14, 35, 17, 22, 14, 25, 20, 64, 14, 38, 40, 17, 14, 45, 25, 22, 14, 27

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.

Links

Table of n, a(n) for n=0..68.

Formula

a(n)=A075473[64n+27], n=0, ..., 256

Example

n=0: 64n+27=27, list={27, 82, 41, 46.23.70, ..}, i.e. the 97th term is the first that <27, the initial value.

Crossrefs

Cf. A074473, A074474, A075476-A075482, A006370.

Sequence in context: A381374 A088866 A244192 * A126146 A112667 A106419

Adjacent sequences: A075475 A075476 A075477 * A075479 A075480 A075481

Keyword

nonn

Author

Labos Elemer, Sep 23 2002

Status

approved