OK, I got the following info (I did NOT know it before!) from looking at 2 charts in the sticky mentioned.
The first chart was the "No Fail Blade Chart" and the second was the first of the two Pegas (manufacturer name) charts:
"No Fail" says for "Dense Hardwood between three quarters and one inch thick" (i.e. roughly the 9 to 18 mm thickness you're talking about) you should try a Reverse Tooth or Spiral Blade, Numbers 5, 6, or 7. The first Pegas chart tells us that their Spiral blades are No. 5 = 35 TPI, No. 6 = 34 TPI, and No. 7 = 28 TPI.
As said I found that out with 2 minutes of looking at those two separate charts. I don't want to sound condescending but if I could do that I'm pretty sure you could have done so too.
And if you don't want to use a Spiral blade but a Reverse Tooth blade instead, then I'll let you look yourself at the 2nd Pegas chart in that sticky which lists the blade numbers and TPIs in their Reverse Tooth blade ranges.
If you don't know what Reverse Tooth is, it's a blade where the first few teeth (down at the bottom of the blade, just where it appears through the blade hole in the table) point UPWARDS instead of DOWNWARDS. This is to try and stop the splintering on the bottom of the wood where the cut first enters the job. Depending on the job I find that works quite well in reducing/eliminating splintering on the bottom of the job.
Personally I like Pegas blades, but as also listed in that sticky, there are other manufacturers too. But if you want to try Pegas, Axminster Tools are their distributor in the UK.
Again I don't want to sound either rude or impatient with you, but there is nothing in the above that you couldn't have found out all by yourself, just as well and just as easily I have.
I also knew nothing when I started (and now I only "know" what suits me), but when I started, before I even know about this Forum, I found out the basics all by myself - and I'm NOT "clever", just a bit more than "vaguely interested". Those charts are not the only source for "converting" blade TPIs into blade numbers BTW - there are at least 2 US sites that have that info (though I forget which now). In my own searches I found those charts on line and put them in the sticky to help newcomers(?) like you.