A121794 This sequence needs a meaningful name.

0, 1, 4, 2, 10, 10, 10, 10, 52, 94, 230, 606, 982, 2194, 4388, 8776, 17552, 86840, 277152, 744616, 2597840, 7412896, 20021472, 17423632, 40042944, 74890208, 459732608, 149780416, 1069245632, 1069245632, 1069245632, 1069245632

Offset

1,3

Links

Table of n, a(n) for n=1..32.

Andrzej Kozlowski, Re: too many special linear matrices, Mathematica forum, 17 August 2006.

Mathematica

SL[n_, p_] := Module[{vars = Table[Unique[ a], {n^2}], iters, mat}, iters = Map[{#, 0, p - 1} &, vars]; mat = Partition[vars, n]; Reap[ Do[If[Det[mat, Modulus -> p] == 1, Sow[mat], Continue[]], Evaluate[Sequence @@ iters]]][[2, 1]]]
a0 = SL[2, 3];
M[n_] := a0[[1 + Mod[n, Length[a0]]]]
v[1] = {0, 1}
v[n_] := v[n] = M[n].v[n - 1]
a = Table[Floor[v[n][[1]]], {n, 1, 50}]

Crossrefs

Sequence in context: A117821 A266851 A185732 * A250108 A210735 A075086

Adjacent sequences: A121791 A121792 A121793 * A121795 A121796 A121797

Keyword

nonn,uned

Author

Roger L. Bagula, Aug 24 2006

Status

approved