The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A003735 Number of perfect matchings (or domino tilings) in W_5 X P_2n. 1
 29, 1189, 49401, 2053641, 85373589, 3549138989, 147544320241, 6133692298001, 254989017189389, 10600368542888629, 440677071050573801, 18319766917914642201, 761586844367955639429, 31660584117320436988989, 1316189472103884945976801, 54716448693989525183595041 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Ars Combin. 49 (1998), 129-154. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..600 F. Faase, On the number of specific spanning subgraphs of the graphs G X P_n, Preliminary version of paper that appeared in Ars Combin. 49 (1998), 129-154. F. Faase, Results from the counting program Index entries for linear recurrences with constant coefficients, signature (44,-102,44,-1). FORMULA a(n) = 44a(n-1) - 102a(n-2) + 44a(n-3) - a(n-4), n>4. G.f.: -x*(x^3-43*x^2+87*x-29)/(x^4-44*x^3+102*x^2-44*x+1). - Colin Barker, Aug 30 2012 MATHEMATICA CoefficientList[Series[-(x^3 - 43 x^2 + 87 x - 29)/(x^4 - 44 x^3 + 102 x^2 - 44 x + 1), {x, 0, 40}], x] (* Vincenzo Librandi, Oct 14 2013 *) LinearRecurrence[{44, -102, 44, -1}, {29, 1189, 49401, 2053641}, 20] (* Harvey P. Dale, Jul 19 2018 *) PROG (MAGMA) I:=[29, 1189, 49401, 2053641]; [n le 4 select I[n] else 44*Self(n-1)-102*Self(n-2)+44*Self(n-3)-Self(n-4): n in [1..20]]; // Vincenzo Librandi, Oct 14 2013 (PARI) Vec(-x*(x^3-43*x^2+87*x-29)/(x^4-44*x^3+102*x^2-44*x+1)+O(x^99)) \\ Charles R Greathouse IV, Jun 23 2020 CROSSREFS Sequence in context: A210303 A268461 A025761 * A159479 A264351 A195740 Adjacent sequences:  A003732 A003733 A003734 * A003736 A003737 A003738 KEYWORD nonn,easy AUTHOR 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 November 30 06:47 EST 2020. Contains 338781 sequences. (Running on oeis4.)