A133508 Record numbers of steps associated with the terms of A133503.

0, 1, 2, 5, 9, 10, 11, 12, 13, 15, 16

Offset

1,3

Comments

This sequence is almost certainly finite.

Links

Table of n, a(n) for n=1..11.

Example

The smallest number that takes 13 steps to converge is 497699, for which the trajectory is 497699 -> 11948427342082473984 -> 23554621393597287150649344 -> 2030652382202824185652602470400000 -> 101921587200000000 -> 38281250 -> 1679616 -> 1452729852 -> 1318305830625 -> 70312500 -> 96 -> 531441 -> 500 -> 0.
The smallest number that takes 15 steps to converge is 3559595 -> for which the trajectory is 3559595 -> 4634857177734375 -> 23122964691361341376561152 -> 1194842734208247398400000000 -> 23554621393597287150649344 -> 2030652382202824185652602470400000 -> 101921587200000000 -> 38281250 -> 1679616 -> 1452729852 -> 1318305830625 -> 70312500 -> 96 -> 531441 -> 500 -> 0.
The number 31395559595973 takes 16 steps to converge and so the next term is >= 16.
The trajectory of 31395559595973 is 31395559595973 -> 471570692025125026702880859375 -> 34755118508614725279865110528 -> 23122964691361341376561152000000 -> 1194842734208247398400000000 -> 23554621393597287150649344 -> 2030652382202824185652602470400000 -> 101921587200000000 -> 38281250 -> 1679616 -> 1452729852 -> 1318305830625 -> 70312500 -> 96 -> 531441 -> 500 -> 0.

Crossrefs

Cf. A133500, A133501, A133503.

Sequence in context: A196408 A091656 A273044 * A125969 A070240 A007369

Adjacent sequences: A133505 A133506 A133507 * A133509 A133510 A133511

Keyword

nonn,base,more

Author

J. H. Conway and N. J. A. Sloane, Dec 04 2007, Dec 18 2007

Extensions

a(11) from Michael S. Branicky, Jan 24 2022

Status

approved