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 A088671 #16 Jul 13 2025 11:08:44 %S A088671 1,12,1053,787320,5208653241,308413053837252,164053436379620039253, %T A088671 784901799876425497055472240,33790882475498615361517892887614321, %U A088671 13091723638887447119952122094399781435115772,45648533143796439623892471646730372987043769546194573 %N A088671 Number of n X n matrices over GF(3) with characteristic polynomial x^(n-1) * (x-1). %H A088671 Irving Reiner, <a href="http://doi.org/10.1215/ijm/1255629830">On the number of matrices with given characteristic polynomial</a>, Illinois Journal of Mathematics, Vol. 5, No. 2 (1961), pp. 324-329. %F A088671 a(n) = (q/(q-1))*(q^(n^2-n)-q^(-2*n+n^2)) where q = 3. %t A088671 a[n_] := (3/2)*(3^(n^2-n) - 3^(n^2-2*n)); Array[a, 10] (* _Amiram Eldar_, Jul 13 2025 *) %Y A088671 Cf. A088668, A088852, A088853. %K A088671 nonn %O A088671 1,2 %A A088671 Yuval Dekel (dekelyuval(AT)hotmail.com) and _W. Edwin Clark_, Nov 29 2003 %E A088671 More terms from _Joerg Arndt_, Oct 04 2013