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

0,2

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

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)

Prog

(PARI) See Links section.

Crossrefs

Cf. A301283.

Sequence in context: A050107 A120068 A015875 * A310042 A310043 A316325

Adjacent sequences: A301282 A301283 A301284 * A301286 A301287 A301288

Keyword

nonn

Author

N. J. A. Sloane, Mar 23 2018

Extensions

More terms from Rémy Sigrist, Mar 28 2018

Status

approved