A299281 Coordination sequence for "reo-e" 3D uniform tiling.

1, 6, 19, 41, 72, 114, 166, 224, 288, 364, 454, 550, 648, 758, 886, 1020, 1152, 1296, 1462, 1634, 1800, 1978, 2182, 2392, 2592, 2804, 3046, 3294, 3528, 3774, 4054, 4340, 4608, 4888, 5206, 5530, 5832, 6146, 6502, 6864, 7200, 7548, 7942, 8342, 8712, 9094, 9526, 9964, 10368

Offset

0,2

Comments

First 20 terms computed by Davide M. Proserpio using ToposPro.

References

B. Grünbaum, Uniform tilings of 3-space, Geombinatorics, 4 (1994), 49-56. See tiling #9.

Links

Colin Barker, Table of n, a(n) for n = 0..1000

Reticular Chemistry Structure Resource (RCSR), The reo-e tiling (or net)

Index entries for linear recurrences with constant coefficients, signature (3,-5,7,-7,5,-3,1).

Formula

G.f.: (x+1)*(x^3+x^2+1)*(x^6-2*x^5+x^4+3*x^2+2*x+1) / ((x^2+1)^2*(1-x)^3). - N. J. A. Sloane, Feb 12 2018

a(n) = 3*a(n-1) - 5*a(n-2) + 7*a(n-3) - 7*a(n-4) + 5*a(n-5) - 3*a(n-6) + a(n-7) for n>8. - Colin Barker, Feb 14 2018

a(n) = (9*n^2 + 4*(1 - A056594(n)) - (n - 4)*A056594(n+1))/2 for n > 3. - Stefano Spezia, Apr 23 2023

Prog

(PARI) Vec((1 + x)*(1 + x^2 + x^3)*(1 + 2*x + 3*x^2 + x^4 - 2*x^5 + x^6) / ((1 - x)^3*(1 + x^2)^2) + O(x^60)) \\ Colin Barker, Feb 14 2018

Crossrefs

See A299282 for partial sums.

The 28 uniform 3D tilings: cab: A299266, A299267; crs: A299268, A299269; fcu: A005901, A005902; fee: A299259, A299265; flu-e: A299272, A299273; fst: A299258, A299264; hal: A299274, A299275; hcp: A007899, A007202; hex: A005897, A005898; kag: A299256, A299262; lta: A008137, A299276; pcu: A005899, A001845; pcu-i: A299277, A299278; reo: A299279, A299280; reo-e: A299281, A299282; rho: A008137, A299276; sod: A005893, A005894; sve: A299255, A299261; svh: A299283, A299284; svj: A299254, A299260; svk: A010001, A063489; tca: A299285, A299286; tcd: A299287, A299288; tfs: A005899, A001845; tsi: A299289, A299290; ttw: A299257, A299263; ubt: A299291, A299292; bnn: A007899, A007202. See the Proserpio link in A299266 for overview.

Cf. A056594.

Sequence in context: A273571 A273778 A173980 * A212684 A035495 A061293

Adjacent sequences: A299278 A299279 A299280 * A299282 A299283 A299284

Keyword

nonn,easy

Author

N. J. A. Sloane, Feb 10 2018

Extensions

a(21)-a(40) from Davide M. Proserpio, Feb 12 2018

Status

approved