login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A298792 Coordination sequence for the bil tiling (or net) with respect to a trivalent node of the first type. 4
1, 3, 6, 9, 11, 14, 19, 22, 23, 25, 30, 35, 35, 36, 41, 46, 49, 49, 52, 57, 60, 63, 64, 67, 71, 74, 79, 80, 81, 85, 90, 95, 93, 94, 101, 106, 109, 107, 110, 117, 120, 123, 122, 125, 131, 134, 139, 138, 139, 145, 150, 155, 151, 152, 161, 166, 169, 165, 168, 177 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Rémy Sigrist, Table of n, a(n) for n = 0..1000

Reticular Chemistry Structure Resource (RCSR), The bil tiling (or net)

Rémy Sigrist, Illustration of first terms

Rémy Sigrist, PARI program for A298792

FORMULA

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

G.f.: (1 + 2*x + 5*x^2 + 7*x^3 + 10*x^4 + 12*x^5 + 15*x^6 + 14*x^7 + 16*x^8 + 14*x^9 + 15*x^10 + 12*x^11 + 10*x^12 + 7*x^13 + 5*x^14 + 2*x^15 + x^16) / ((1 - x)^2*(1 + x^2)*(1 - x + x^2 - x^3 + x^4)*(1 + x + x^2 + x^3 + x^4)^2).

a(n) = a(n-1) - 2*a(n-2) + 2*a(n-3) - 2*a(n-4) + 3*a(n-5) - 3*a(n-6) + 4*a(n-7) - 4*a(n-8) + 4*a(n-9) - 3*a(n-10) + 3*a(n-11) - 2*a(n-12) + 2*a(n-13) - 2*a(n-14) + a(n-15) - a(n-16) for n>16.

(End)

PROG

(PARI) See Links section.

CROSSREFS

Cf. A298793, A298794, A298795.

Sequence in context: A151926 A166265 A145283 * A177800 A310147 A310148

Adjacent sequences: A298789 A298790 A298791 * A298793 A298794 A298795

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 27 2018

EXTENSIONS

More terms from Rémy Sigrist, Mar 30 2018

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 29 16:39 EST 2022. Contains 358431 sequences. (Running on oeis4.)