A174089 Number of spanning trees in C_11 X P_n.

11, 10759331, 4435600730891, 1584603178322856659, 545701094921321191290251, 185861400461684004931359802019, 63080339061067311398935095930531419, 21384626538080492686675351682716886393459

Offset: 1

Author

Alois P. Heinz, Nov 26 2010

Keywords

• nonn
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..180
• Eric Weisstein's World of Mathematics, Cycle Graph
• Eric Weisstein's World of Mathematics, Path Graph
• Eric Weisstein's World of Mathematics, Spanning Tree

Crossrefs

11th column of A173958.

Cf. A000012, A001542, A003690, A003753, A003733, A158880, A158898.

Programs

Maple

a:= n-> 11* (Matrix([[0, 1, 989, 635009, 379545563, 222731206721, 129986502957277, 75726985139241127, 44091461282285910613, 25667108238650778993721, 14940759758135641310394029, 8696803311384043382138568704, 5062251640287899331740697744283, 2946638531103878161891572927216367, 1715179927870529863091149494541065923, 998372029710787510889689081784904921409, 581132402632124482558541496059410958698763][1+abs(i)]*
signum(-i)$i=-15..16]). Matrix(32, (i, j)-> if i=j-1 then 1 elif j=1 then [[-9866686348925002518, 8584218556222705486, -5646220475933195574, 2797526034931937278, -1038052511465703094, 286230180847745070, -58096997326051905, 8585065341436957, -911803001143321, 68534901051869, -3574487862001, 125866549709, -2870938929, 39687581, -297177, 989, -1] [1+abs(k)]$k=-15..16][i] else 0 fi)^n)[1, 16]^2: seq(a(n), n=1..20);

Formula

See program.