A165106 Consider the base-8 Kaprekar map x->K(x) described in A165090. Sequence gives the smallest number that belongs to a cycle of length n under repeated iteration of this map, or -1 if there is no cycle of length n.

0, 17892, 1589, 21483, 1022, 7034104602, 1445787

Offset: 1

Author

Joseph Myers, Sep 04 2009

Keywords

• base
• nonn

Comments

Known values (to 70 base-8 digits):

a(1) = 0 (base 10) = 0 (base 8)

a(2) = 17892 (base 10) = 42744 (base 8)

a(3) = 1589 (base 10) = 3065 (base 8)

a(4) = 21483 (base 10) = 51753 (base 8)

a(5) = 1022 (base 10) = 1776 (base 8)

a(6) = 7034104602 (base 10) = 64320765432 (base 8)

a(7) = 1445787 (base 10) = 5407633 (base 8)

a(9) = 467364965130 (base 10) = 6632107665412 (base 8)

a(12) = 29921040357642 (base 10) = 663321076654412 (base 8)

Links

• Index entries for the Kaprekar map

Crossrefs

Cf. A165090, A165094, A165095, A165097, A165099, A165101.

In other bases: A153881 (base 2), A165008 (base 3), A165028 (base 4), A165047 (base 5), A165067 (base 6), A165086 (base 7), A165126 (base 9), A151959 (base 10).