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 A229740 #9 Aug 22 2020 17:32:26 %S A229740 1,352,9909,107776,698125,12045817,37679104,103495401,584190541, %T A229740 2487920149,15207694336,25846158097,68520305701,367691205289, %U A229740 766959765625,1513188079677,2846113596901,5135516500321,6803021627392,24650159312557,61346708983561,93685639700269,206700247118737,299545983486001 %N A229740 a(n) = q^9/6+5*q^8/6+2*q^7/3-q^6/6-5*q^5/6+q^4/3 where q = n-th prime power A000961(n). %H A229740 L. Kaylor, D. Offner, <a href="https://projecteuclid.org/euclid.involve/1513733722">Counting matrices over a finite field with all eigenvalues in the field</a>, Involve, a Journal of Mathematics, Vol. 7 (2014), No. 5, 627-645. [<a href="http://dx.doi.org/10.2140/involve.2014.7.627">DOI</a>] %Y A229740 Cf. A000961, A229738, A229739, A255500, A255501. %K A229740 nonn %O A229740 1,2 %A A229740 _N. J. A. Sloane_, Oct 05 2013