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.

A367526 The number of ways of tiling the n X n grid up to diagonal and antidiagonal reflections by two tiles that are each fixed under both of these reflections.

Original entry on oeis.org

2, 9, 168, 16960, 8407040, 17180983296, 140737630961664, 4611686053860868096, 604462909825456529211392, 316912650057075646247661993984, 664613997892457973921852429862699008, 5575186299632655785536225887234636434636800, 187072209578355573530072906199130068813267662274560
Offset: 1

Views

Author

Peter Kagey, Dec 10 2023

Keywords

Crossrefs

Programs

  • Mathematica
    Table[{2^(2 m^2 - 4 m - 1) (4^m + 4^m^2 + 8^m), 4^(m^2 - 1) (1 + 2^(1 + m) + 4^m^2)}, {m, 1, 5}] // Flatten

Formula

a(2m-1) = 2^(2m^2 - 4m - 1)(4^m + 4^m^2 + 8^m).
a(2m) = 4^(m^2 - 1)(1 + 2^(1 + m) + 4^m^2).

A367528 The number of ways of tiling the n X n grid up to diagonal and antidiagonal reflections by a tile that is fixed under 180-degree rotations but is not fixed under either reflection.

Original entry on oeis.org

1, 5, 136, 16448, 8390656, 17179934720, 140737496743936, 4611686019501129728, 604462909807864343166976, 316912650057057631849152512000, 664613997892457937028364282443595776, 5575186299632655785385110159782807787798528, 187072209578355573530071668259090783432992763150336
Offset: 1

Views

Author

Peter Kagey, Dec 10 2023

Keywords

Crossrefs

Programs

  • Mathematica
    Table[{2^(2 m^2 - 4 m - 1) (4^m + 4^m^2), (4^m^2 + 16^m^2)/4}, {m, 1, 5}] // Flatten

Formula

a(2m-1) = 2^(2m^2 - 4m - 1)*(4^m + 4^m^2).
a(2m) = (4^m^2 + 16^m^2)/4.

A368142 Number of ways of tiling the n X n torus up to diagonal and antidiagonal reflection of the square by an asymmetric tile.

Original entry on oeis.org

1, 23, 7296, 67124308, 11258999068672, 32794211700912270688, 1616901275801313012113145856, 1329227995784915876578744356684451904, 18043230090504974298810923860695296894480941056, 4017345110647475688854905231100098373350012274109805442048
Offset: 1

Views

Author

Peter Kagey, Dec 16 2023

Keywords

Crossrefs

Programs

  • Mathematica
    A368142[n_] := 1/(4 n^2)*(DivisorSum[n, Function[d, DivisorSum[n, Function[c, EulerPhi[c] EulerPhi[d] 4^(n^2/LCM[c, d])]]]] + n^2*If[EvenQ[n], (3*2^(n^2 - 2)), 0] + 2*n*DivisorSum[n, Function[d, EulerPhi[d]*If[EvenQ[d], 2^(n^2/d), 0]]])

A367527 The number of ways of tiling the n X n grid up to diagonal and antidiagonal reflections by a tile that is fixed under diagonal reflection, but not antidiagonal reflection.

Original entry on oeis.org

1, 7, 144, 16704, 8396800, 17180459008, 140737555464192, 4611686036680998912, 604462909816110680375296, 316912650057066639048407252992, 664613997892457954898647603849723904, 5575186299632655785460668023508722111217664, 187072209578355573530072277557703869206096815063040
Offset: 1

Views

Author

Peter Kagey, Dec 10 2023

Keywords

Crossrefs

Programs

  • Mathematica
    Table[{2^(2 m^2 - 4 m - 2) (2^(1 + 2 m^2) + 8^m), 4^(m^2 - 1) (1 + 2^m + 4^m^2)}, {m, 1, 5}] // Flatten

Formula

a(2m-1) = 2^(2m^2 - 4m - 2)*(2^(1 + 2 m^2) + 8^m).
a(2m) = 4^(m^2 - 1)*(1 + 2^m + 4^m^2).

A367532 The number of ways of tiling the n X n grid up to 90-degree rotation by a tile that is not fixed under 180-degree rotation.

Original entry on oeis.org

1, 70, 65536, 1073758336, 281474976710656, 1180591620734591303680, 79228162514264337593543950336, 85070591730234615870455337878516924416, 1461501637330902918203684832716283019655932542976, 401734511064747568885490523085607563280607806359022338048000
Offset: 1

Views

Author

Peter Kagey, Dec 11 2023

Keywords

Crossrefs

Programs

  • Mathematica
    Table[{256^(m^2 - m), 4^(m^2 - 1)*(2 + 4^m^2 + 64^m^2)}, {m, 1, 5}] // Flatten

Formula

a(2*n-1) = 256^(n^2 - n).
a(2*n) = 4^(n^2 - 1)*(2 + 4^n^2 + 64^n^2).
Showing 1-5 of 5 results.