A174001 Number of spanning trees in C_9 X P_n.

9, 632025, 23057815104, 763341471963225, 24743382596536452489, 797880028172050676793600, 25694231385152383926116001849, 827147402338052897443922764419225, 26625078176206788678765153788526329856

Offset: 1

Author

Alois P. Heinz, Nov 26 2010

Keywords

• nonn
• easy

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..70
• 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

9th column of A173958.

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

Programs

Maple

a:= n-> 9* (Matrix([[0, 1, 265, 50616, 9209545, 1658090689, 297747101520, 53431400864569, 9586723471888105][1+abs(i)]$i=-7..8]). Matrix(16, (i, j)-> if i=j-1 then 1 elif j=1 then [[-427427424, 327381265, -146975161, 38357160, -5699687, 457655, -17736, 265, -1][1+abs(k)]$k=-7..8][i] else 0 fi)^n)[1, 8]^2: seq(a(n), n=1..20);

Formula

See program.