This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A060868 #30 Dec 26 2024 16:57:58
%S A060868 2,32,338,3200,29282,264992,2389298,21516800,193690562,1743333152,
%T A060868 15690352658,141214236800,1270931319842,11438391444512,
%U A060868 102945551698418,926510051379200,8338590720693122,75047317261079072,675425857674234578,6078832726041680000,54709494555295826402
%N A060868 Number of n X n matrices over GF(3) with rank 1.
%H A060868 Harry J. Smith, <a href="/A060868/b060868.txt">Table of n, a(n) for n = 1..200</a>
%H A060868 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (13,-39,27).
%F A060868 a(n) = 1/2 * (3^n - 1)^2.
%F A060868 G.f.: -2*x*(3*x+1) / ((x-1)*(3*x-1)*(9*x-1)). - _Colin Barker_, Dec 23 2012
%F A060868 E.g.f.: exp(x)*(1 - 2*exp(2*x) + exp(8*x))/2. - _Stefano Spezia_, Dec 26 2024
%e A060868 a(2) = 32 because there are 33 (the second element in sequence A060705) singular 2 X 2 matrices over GF(3), that have rank <= 1 of which only the zero matrix has rank zero so a(2) = 33 - 1 = 32.
%o A060868 (PARI) a(n) = { (3^n - 1)^2 / 2 } \\ _Harry J. Smith_, Jul 13 2009
%Y A060868 Column k=3 of A379587.
%Y A060868 Cf. A060705, A060867, A060869, A238976.
%K A060868 nonn,easy
%O A060868 1,1
%A A060868 Ahmed Fares (ahmedfares(AT)my-deja.com), May 04 2001
%E A060868 More terms from _Jason Earls_, May 05 2001