A301285 Coordination sequence for node of type V2 in "car" 2-D tiling (or net).

1, 3, 6, 10, 12, 14, 20, 23, 22, 27, 34, 34, 34, 40, 46, 47, 46, 51, 60, 60, 56, 64, 74, 71, 68, 77, 86, 84, 80, 88, 100, 97, 90, 101, 114, 108, 102, 114, 126, 121, 114, 125, 140, 134, 124, 138, 154, 145, 136, 151, 166, 158, 148, 162, 180, 171, 158, 175, 194

Offset: 0

Author

N. J. A. Sloane, Mar 23 2018

Keywords

• nonn

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..1000
• Reticular Chemistry Structure Resource (RCSR), The car tiling (or net)
• Rémy Sigrist, Illustration of first terms
• Rémy Sigrist, PARI program for A301285

Crossrefs

Cf. A301283.

Programs

PARI

See Links section.

Formula

Conjectures from Colin Barker, Mar 30 2018: (Start)

G.f.: (1 + 2*x + 5*x^2 + 7*x^3 + 7*x^4 + 7*x^5 + 5*x^6 + 2*x^7 + x^8) / ((1 - x)^2*(1 + x^2)^2*(1 + x + x^2)).

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

(End)

Extensions

More terms from Rémy Sigrist, Mar 28 2018