I have shelves of textbooks sitting around. Multiple calculus, algebra, trig, stats, math for elementary school teachers. Several on topology, discrete math, complex analysis…
Most are subjects I took in college (though most aren’t the books I used), but not all.
I really do intend to redo my linear algebra stuff sometime. That was my favourite math course because it all fit together so coherently, the way math really is supposed to. It’s the opposite of statistics.

