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.

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A336724 Number of n-step self-avoiding walks on the half-Manhattan square lattice.

Original entry on oeis.org

1, 3, 7, 17, 37, 83, 181, 399, 863, 1887, 4057, 8797, 18851, 40649, 86911, 186705, 398413, 853407, 1818099, 3885377, 8266359, 17632961, 37473467, 79814011, 169457991, 360469139, 764700473, 1624915019, 3444615545, 7312733017, 15492242679, 32862908109, 69581860921, 147497088201
Offset: 0

Views

Author

Sean A. Irvine, Aug 01 2020

Keywords

Comments

In the half-Manhattan lattice, E-W streets run alternately E and W, but N-S streets are two way.

Crossrefs

Cf. A336705 (coordination sequence), A336742 (self-avoiding cycles), A117633 (Manhattan lattice), A001411 (square lattice), A322419 (L-lattice).

A336705 Coordination sequence for the half-Manhattan lattice.

Original entry on oeis.org

1, 3, 7, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144, 148, 152, 156, 160, 164, 168, 172, 176, 180, 184, 188, 192, 196, 200, 204, 208, 212, 216, 220, 224, 228
Offset: 0

Views

Author

Sean A. Irvine, Jul 31 2020

Keywords

Comments

In the half-Manhattan lattice, E-W streets run alternately E and W, but N-S streets are two way.

Crossrefs

Cf. A336627 (Manhattan lattice), A008574 (square lattice), A336726 (self-avoiding walks), A336742 (self-avoiding cycles).

Programs

  • Mathematica
    LinearRecurrence[{2,-1},{1,3,7,12,16},100] (* Paolo Xausa, Sep 01 2023 *)

Formula

G.f.: (1+x) * (1+2*x^2-x^3) / (1-x)^2.
a(n) = 4*n, n >= 3.
Showing 1-2 of 2 results.