OFFSET
0,3
LINKS
Per Hakan Lundow, Computation of matching polynomials and the number of 1-factors in polygraphs, Research report, No 12, 1996, Department of Math., Umea University, Sweden.
Per Hakan Lundow, Enumeration of matchings in polygraphs, 1998.
Sergey Perepechko, Generation function
Index entries for linear recurrences with constant coefficients, signature (1, 1065, 2271, -313647, -581107, 42290089, 46394373, -3142067439, -1204065921, 141122117137, -23552838575, -4048343500561, 2177821303792, 77145898134992, -57692927620568, -1009771490156144, 834602390555152, 9348345877875672, -7534201668856784, -62671184060029400, 44881022619918032, 309385807529385808, -180904763263594728, -1136378367751634480, 495365037290693552, 3121850377815899650, -901764108815772034, -6426469969210271370, 1005943422942920850, 9913854106266511726, -456766693621948514, -11455967606609256194, -456766693621948514, 9913854106266511726, 1005943422942920850, -6426469969210271370, -901764108815772034, 3121850377815899650, 495365037290693552, -1136378367751634480, -180904763263594728, 309385807529385808, 44881022619918032, -62671184060029400, -7534201668856784, 9348345877875672, 834602390555152, -1009771490156144, -57692927620568, 77145898134992, 2177821303792, -4048343500561, -23552838575, 141122117137, -1204065921, -3142067439, 46394373, 42290089, -581107, -313647, 2271, 1065, 1, -1).
MATHEMATICA
t[m_, n_] := Product[2*(2 + Cos[2*j*Pi/(m+1)] + Cos[2*k*Pi/(n+1)]), {k, 1, n/2}, {j, 1, m/2}]; a[n_] := N[t[n, 12], 16] // Round; Table[a[n], {n, 1, 15}] (* Jean-François Alcover, Dec 20 2012, after A099390 *)
PROG
(PARI) {a(n) = sqrtint(polresultant(polchebyshev(12, 2, x/2), polchebyshev(n, 2, I*x/2)))} \\ Seiichi Manyama, Apr 13 2020
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved