%I A003698
%S A003698 1,9,53,341,2169,13825,88093,561357,3577121,22794425,145252485,
%T A003698 925589701,5898117961,37584466929,239498796653,1526153708861,
%U A003698 9725080775409,61970950592425,394896331045333,2516390514947637
%N A003698 Number of 2-factors in C_4 X P_n.
%D A003698 F. Faase, On the number of specific spanning subgraphs of the graphs 
               G X P_n, Ars Combin. 49 (1998), 129-154.
%H A003698 F. Faase, <a href="http://www.iwriteiam.nl/Cpaper.zip">On the number 
               of specific spanning subgraphs of the graphs G X P_n</a>, Preliminary 
               version of paper that appeared in Ars Combin. 49 (1998), 129-154.
%H A003698 F. Faase, <a href="http://www.iwriteiam.nl/counting.html">Counting Hamilton 
               cycles in product graphs</a>
%H A003698 F. Faase, <a href="http://www.iwriteiam.nl/Cresults.html">Results from 
               the counting program</a>
%H A003698 F. Faase, <a href="http://home.wxs.nl/~faase009/counting.html">Counting 
               Hamilton cycles in product graphs</a>
%F A003698 a(n) = 6a(n-1) + 3a(n-2) - 4a(n-3), n>3.
%Y A003698 Sequence in context: A122588 A005025 A038761 this_sequence A001688 A144040 
               A052108
%Y A003698 Adjacent sequences: A003695 A003696 A003697 this_sequence A003699 A003700 
               A003701
%K A003698 nonn
%O A003698 1,2
%A A003698 Frans Faase (Frans_LiXia(AT)wxs.nl)