This site is supported by donations to The OEIS Foundation.

 Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A198310 Moore lower bound on the order of a (10,g)-cage. 15
 11, 20, 101, 182, 911, 1640, 8201, 14762, 73811, 132860, 664301, 1195742, 5978711, 10761680, 53808401, 96855122, 484275611, 871696100, 4358480501, 7845264902, 39226324511, 70607384120, 353036920601, 635466457082, 3177332285411 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,1 LINKS Gordon Royle, Cages of higher valency Index entries for linear recurrences with constant coefficients, signature (1,9,-9). FORMULA a(2i) = 2 sum_{j=0}^{i-1}9^j =  string "2"^i read in base 9. a(2i+1) = 9^i +  2 sum_{j=0}^{i-1}9^j = string "1"*"2"^i read in base 9. a(n) = (-3-(-3)^n+4*3^n)/12. a(n) = a(n-1)+9*a(n-2)-9*a(n-3). G.f.: -x^3*(18*x^2-9*x-11) / ((x-1)*(3*x-1)*(3*x+1)). - Colin Barker, Feb 01 2013 PROG (PARI) a(n)=(-3-(-3)^n+4*3^n)/12 \\ Charles R Greathouse IV, Jul 06 2017 CROSSREFS Moore lower bound on the order of a (k,g) cage: A198300 (square); rows: A000027 (k=2), A027383 (k=3), A062318 (k=4), A061547 (k=5), A198306 (k=6), A198307 (k=7), A198308 (k=8), A198309 (k=9), this sequence (k=10), A094626 (k=11); columns: A020725 (g=3), A005843 (g=4), A002522 (g=5), A051890 (g=6), A188377 (g=7). Sequence in context: A067969 A068599 A180113 * A085187 A061384 A071154 Adjacent sequences:  A198307 A198308 A198309 * A198311 A198312 A198313 KEYWORD nonn,easy,base AUTHOR Jason Kimberley, Oct 30 2011 STATUS approved

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

Last modified December 11 02:05 EST 2018. Contains 318049 sequences. (Running on oeis4.)