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%I #8 Aug 22 2020 17:32:39
%S 1,14,63,184,425,1519,2528,3969,8591,16393,36736,46529,71839,151823,
%T 210625,285039,377609,491071,556544,987049,1480961,1787983,2542559,
%U 2998849,4092713,6262319,7148041,8648704,10374079,13061231,14585473,19964959,22051521,24297503,32072129,45172609,53055401,57362863,66759119
%N a(n) = q^2*(q^2+2*q-1)/2, where q = n-th prime power A000961(n).
%H 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 Cf. A000961, A229738.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Oct 05 2013