A164736 Number of n-digit cycles of length 5 under the Kaprekar map A151949

0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 3, 0, 5, 0, 6, 0, 6, 1, 6, 3, 6, 5, 6, 6, 6, 6, 7, 6, 9, 6, 11, 6, 12, 6, 12, 7, 12, 9, 12, 11, 12, 12, 12, 12, 13, 12, 15, 12, 17, 12, 18, 12, 18, 13, 18, 15, 18, 17, 18, 18, 18, 18, 19, 18, 21, 18, 23, 18, 24, 18, 24, 19, 24, 21, 24, 23, 24, 24, 24

Offset

1,13

Links

Joseph Myers, Table of n, a(n) for n=1..140

Index entries for the Kaprekar map

Formula

Conjectures from Chai Wah Wu, Apr 13 2024: (Start)

a(n) = a(n-1) + a(n-2) - 2*a(n-3) + a(n-4) + a(n-5) - 2*a(n-6) + a(n-7) + a(n-8) - a(n-9) for n > 15.

G.f.: x^11*(x^2 + 1)*(x^2 - x + 1)/((x - 1)^2*(x + 1)*(x^6 + x^3 + 1)). (End)

Crossrefs

Cf. A151949, A164727, A164728, A164731, A164732, A164733, A164734, A164735.

Sequence in context: A347361 A175919 A086664 * A378450 A349343 A109753

Adjacent sequences: A164733 A164734 A164735 * A164737 A164738 A164739

Keyword

base,nonn

Author

Joseph Myers, Aug 23 2009

Status

approved