cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 10 results.

A164731 Number of cycles of n-digit numbers (including fixed points) under the Kaprekar map A151949.

Original entry on oeis.org

1, 0, 1, 1, 3, 3, 1, 4, 3, 8, 3, 16, 5, 27, 8, 46, 9, 73, 11, 110, 16, 162, 25, 231, 37, 318, 58, 429, 88, 572, 132, 747, 192, 963, 269, 1229, 372, 1551, 500, 1939, 662, 2401, 864, 2948, 1115, 3586, 1421, 4330, 1792, 5194, 2240, 6191, 2764, 7338, 3382, 8650, 4105
Offset: 1

Views

Author

Joseph Myers, Aug 23 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165025 (base 4), A165045 (base 5), A165064 (base 6), A165084 (base 7), A165103 (base 8), A165123 (base 9). [Joseph Myers, Sep 05 2009]

A165099 Consider the base-8 Kaprekar map n->K(n) defined in A165090. Sequence gives least elements of each cycle, including fixed points.

Original entry on oeis.org

0, 21, 252, 1022, 1589, 17892, 21483, 102837, 147420, 213402, 1445787, 1707930, 1711962, 6589877, 13667738, 16092433, 76545756, 93093147, 110132442, 111443346, 421817781, 874802586, 878996762, 1029991697, 1068263553
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Comments

Initial terms in base 8: 0, 25, 374, 1776, 3065, 42744, 51753, 310665, 437734, 640632.

Crossrefs

In other bases: A163205 (base 2), A165002 (base 3), A165021 (base 4), A165041 (base 5), A165060 (base 6), A165080 (base 7), A165119 (base 9), A164718 (base 10).

A165025 Number of cycles of n-digit numbers (including fixed points) under the base-4 Kaprekar map A165012.

Original entry on oeis.org

1, 0, 1, 2, 1, 3, 1, 4, 3, 5, 4, 8, 5, 10, 8, 12, 10, 16, 12, 19, 16, 22, 19, 27, 22, 31, 27, 35, 31, 41, 35, 46, 41, 51, 46, 58, 51, 64, 58, 70, 64, 78, 70, 85, 78, 92, 85, 101, 92, 109, 101, 117, 109, 127, 117, 136, 127, 145, 136, 156, 145, 166, 156, 176, 166, 188, 176
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165045 (base 5), A165064 (base 6), A165084 (base 7), A165103 (base 8), A165123 (base 9), A164731 (base 10).

Formula

Conjectures from Colin Barker, Jun 01 2017: (Start)
G.f.: x*(1 - x^2 + x^3 - 2*x^6 + 3*x^8 - x^10) / ((1 - x)^3*(1 + x)^2*(1 + x + x^2)).
a(n) = 2*a(n-2) + a(n-3) - a(n-4) - 2*a(n-5) + a(n-7) for n>7.
(End)

A165064 Number of cycles of n-digit numbers (including fixed points) under the base-6 Kaprekar map A165051.

Original entry on oeis.org

1, 0, 1, 1, 2, 4, 1, 5, 2, 7, 3, 9, 4, 13, 7, 17, 8, 24, 11, 30, 16, 37, 21, 46, 27, 57, 34, 68, 42, 83, 52, 96, 64, 113, 77, 132, 90, 153, 107, 175, 125, 200, 145, 226, 168, 256, 191, 288, 217, 323, 247, 358, 278, 399, 312, 441, 348, 487, 387, 536, 429, 587, 475, 641
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165025 (base 4), A165045 (base 5), A165084 (base 7), A165103 (base 8), A165123 (base 9), A164731 (base 10).

Formula

G.f.: x*(1 + x + 2*x^5 - 2*x^7 - 3*x^8 - 3*x^9 - x^10 + 2*x^11 + 4*x^12 + 4*x^13 + 4*x^14 + x^15 - 3*x^16 - 3*x^17 - 2*x^18 - x^19 + x^21 + x^22) / ((1 - x)^4*(1 + x)^3*(1 + x^2)*(1 + x + x^2)*(1 + x + x^2 + x^3 + x^4)) (conjectured). - Colin Barker, Jun 01 2017

A165104 Number of n-digit numbers in a cycle (including fixed points) under the base-8 Kaprekar map A165090.

Original entry on oeis.org

1, 1, 1, 8, 6, 5, 12, 7, 15, 13, 12, 31, 14, 40, 14, 59, 12, 96, 11, 137, 24, 184, 35, 234, 64, 300, 102, 391, 134, 494, 175, 630, 232, 782, 311, 954, 402, 1147, 521, 1374, 659, 1649, 814, 1943, 992, 2294, 1203, 2687, 1454, 3117, 1731, 3597, 2060, 4130, 2430, 4734
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165007 (base 3), A165026 (base 4), A165046 (base 5), A165065 (base 6), A165085 (base 7), A165124 (base 9), A164732 (base 10).

A165006 Number of cycles of n-digit numbers (including fixed points) under the base-3 Kaprekar map A164993.

Original entry on oeis.org

1, 0, 0, 1, 1, 1, 2, 1, 3, 2, 5, 2, 6, 3, 7, 4, 10, 5, 12, 6, 13, 7, 16, 8, 17, 9, 19, 10, 22, 11, 23, 14, 26, 15, 30, 16, 33, 18, 34, 19, 37, 20, 39, 23, 42, 24, 47, 25, 48, 26, 50, 28, 55, 29, 56, 32, 59, 33, 63, 34, 64, 37, 65, 40, 72, 41, 78, 44, 79, 46, 82, 49, 83, 51, 87, 52
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165025 (base 4), A165045 (base 5), A165064 (base 6), A165084 (base 7), A165103 (base 8), A165123 (base 9), A164731 (base 10).

A165045 Number of cycles of n-digit numbers (including fixed points) under the base-5 Kaprekar map A165032.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 3, 2, 6, 3, 9, 2, 14, 2, 16, 4, 23, 4, 26, 4, 30, 5, 36, 7, 40, 11, 54, 11, 68, 14, 77, 16, 83, 18, 95, 19, 107, 25, 126, 27, 144, 29, 150, 30, 160, 33, 188, 35, 196, 41, 209, 42, 238, 46, 247, 50, 257, 63, 313, 64, 367, 78, 378, 82, 397, 91
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165025 (base 4), A165064 (base 6), A165084 (base 7), A165103 (base 8), A165123 (base 9), A164731 (base 10).

A165084 Number of cycles of n-digit numbers (including fixed points) under the base-7 Kaprekar map A165071.

Original entry on oeis.org

1, 0, 1, 1, 1, 1, 1, 1, 1, 3, 1, 2, 3, 2, 4, 2, 5, 1, 8, 6, 10, 5, 13, 7, 18, 7, 20, 8, 25, 12, 30, 13, 35, 15, 43, 16, 51, 20, 56, 25, 63, 29, 71, 33, 79, 38, 89, 42, 99, 48, 112, 53, 123, 57, 137, 63, 150, 71, 164, 79, 177, 87, 190, 95, 210, 101, 229, 109, 246, 119, 263, 132, 280
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165025 (base 4), A165045 (base 5), A165064 (base 6), A165103 (base 8), A165123 (base 9), A164731 (base 10).

A165123 Number of cycles of n-digit numbers (including fixed points) under the base-9 Kaprekar map A165110.

Original entry on oeis.org

1, 1, 1, 2, 2, 1, 1, 2, 2, 3, 2, 3, 3, 3, 4, 2, 4, 4, 5, 4, 6, 5, 9, 4, 15, 4, 15, 5, 18, 5, 19, 7, 23, 5, 30, 6, 32, 8, 32, 8, 34, 11, 34, 11, 39, 12, 42, 14, 43, 15, 44, 17, 50, 19, 54, 22, 57, 22, 63, 21, 64, 23, 68, 29, 95, 26, 127, 34, 130, 34
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A165006 (base 3), A165025 (base 4), A165045 (base 5), A165064 (base 6), A165084 (base 7), A165103 (base 8), A164731 (base 10).

A165105 Number of n-digit fixed points under the base-8 Kaprekar map A165090.

Original entry on oeis.org

1, 1, 1, 0, 0, 2, 1, 1, 1, 1, 0, 4, 0, 4, 2, 2, 2, 4, 2, 3, 6, 5, 2, 7, 2, 6, 5, 10, 5, 8, 5, 8, 7, 9, 11, 12, 7, 11, 9, 12, 9, 21, 10, 14, 12, 15, 13, 18, 20, 18, 15, 20, 15, 23, 16, 30, 20, 23, 20, 26, 21, 27, 32, 29, 23, 32, 25, 32, 28, 43
Offset: 1

Views

Author

Joseph Myers, Sep 04 2009

Keywords

Crossrefs

In other bases: A004526 (base 2, adjusted to start 1, 0, 0, 1, 1, ...), A008615 (base 3), A165027 (base 4), A008617 (base 5), A165066 (base 6), A008722 (base 7, conjecturally), A165125 (base 9), A164733 (base 10).

Formula

Conjectures from Chai Wah Wu, Apr 13 2024: (Start)
a(n) = - a(n-1) + a(n-3) + 2*a(n-4) + 2*a(n-5) + a(n-6) - a(n-7) - 2*a(n-8) - 2*a(n-9) - a(n-10) + a(n-12) + a(n-13) for n > 15.
G.f.: x*(-x^14 + x^8 - x^5 + x^4 - x^2 - x - 1)/((x - 1)^3*(x + 1)^2*(x^2 + 1)*(x^2 + x + 1)*(x^4 + x^3 + x^2 + x + 1)). (End)
Showing 1-10 of 10 results.