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 1-5 of 5 results.

A361294 A variant of payphone permutations: given a circular booth with n payphones, one of which is already occupied, a(n) is the number ways for n-1 people to choose the payphones in order, where each person chooses an unoccupied payphone such that the closest occupied payphone is as distant as possible, and a payphone adjacent to a single occupied payphone is preferred over a payphone sandwiched between two occupied payphones.

Original entry on oeis.org

1, 1, 2, 2, 8, 16, 24, 48, 192, 1536, 4608, 18432, 23040, 92160, 241920, 1935360, 3870720, 41287680, 371589120, 11890851840, 29727129600, 237817036800, 1248539443200, 19976631091200, 11236854988800, 42807066624000, 176579149824000, 3390319676620800, 6886586843136000
Offset: 1

Views

Author

Max Alekseyev, Apr 10 2023

Keywords

Comments

Provides the same counts as A095239, but up to a choice for the first payphone.

Crossrefs

Formula

a(n) = A095239(n) / n = A095240(n+1) / 2.

A361295 A variant of payphone permutations: given a row of n payphones, a(n) is the number ways for n people to choose the payphones in order, where each person chooses an unoccupied payphone such that the closest occupied payphone is as distant as possible, and among the available payphones adjacent to a single occupied payphone the most preferred are payphones at open ends.

Original entry on oeis.org

1, 2, 4, 6, 12, 40, 144, 384, 1008, 6816, 33600, 115200, 783360, 3024000, 16450560, 140636160, 558351360, 2262435840, 29599395840, 180278784000, 2124328550400, 13664957644800, 127667338444800, 852837440716800, 11377123378790400, 116737211695104000, 816490952589312000
Offset: 1

Views

Author

Max Alekseyev, Apr 08 2023

Keywords

Crossrefs

Extensions

Definition corrected by Max Alekseyev, Jun 21 2023

A361296 A variant of payphone permutations: given a circular booth with n payphones, a(n) is the number ways for n people to choose the payphones in order, where each person chooses an unoccupied payphone such that the closest occupied payphone is as distant as possible.

Original entry on oeis.org

1, 2, 6, 8, 60, 144, 336, 384, 8640, 57600, 221760, 967680, 4193280, 9031680, 14515200, 30965760, 2368880640, 50164531200, 582465945600, 7357464576000, 50214695731200, 245494068019200, 1443672502272000, 24103053950976000, 200858782924800000, 835572536967168000
Offset: 1

Views

Author

Max Alekseyev, Apr 08 2023

Keywords

Crossrefs

A362192 A variant of payphone permutations: given a circular booth with n payphones, one of which is already occupied, a(n) is the number ways for n-1 people to choose the payphones in order, where each person chooses an unoccupied payphone such that the closest occupied payphone is as distant as possible.

Original entry on oeis.org

1, 1, 2, 2, 12, 24, 48, 48, 960, 5760, 20160, 80640, 322560, 645120, 967680, 1935360, 139345920, 2786918400, 30656102400, 367873228800, 2391175987200, 11158821273600, 62768369664000, 1004293914624000, 8034351316992000, 32137405267968000, 96412215803904000, 385648863215616000, 964122158039040000, 1928244316078080000
Offset: 1

Views

Author

Max Alekseyev, Apr 10 2023

Keywords

Comments

Provides the same counts as A361296, but up to a choice for the first payphone.

Crossrefs

Formula

a(n) = A361296(n) / n.

A363785 A variant of payphone permutations: given a row of n payphones, a(n) is the number ways for n people to choose the payphones in order, where each person chooses an unoccupied payphone such that the closest occupied payphone is as distant as possible, and a payphone adjacent to a single occupied payphone is preferred over a payphone sandwiched between two occupied payphones.

Original entry on oeis.org

1, 2, 4, 6, 16, 28, 120, 264, 576, 2784, 11040, 37440, 204672, 679680, 2511360, 15655680, 52945920, 232796160, 2456801280, 11867627520, 97875025920, 576737280000, 4012233523200, 20013325516800, 215802239385600, 1778700504268800, 9687506721177600, 88613303353344000, 448250987623219200
Offset: 1

Views

Author

Max Alekseyev, Jun 21 2023

Keywords

Crossrefs

Showing 1-5 of 5 results.