UTF-8 byte meanings

-0-1-2-3-4-5-6-7-8-9-A-B-C-D-E-F
0-NULSOHSTXETXEOTENQACKBELBSTABLFVTFFCRSOSI
1-DLEDC1DC2DC3DC4NAKSYNETBCANEMSUBESCFSGSRSUS
2- !"#$%&'()*+,-./
3-0123456789:;<=>?
4-@ABCDEFGHIJKLMNO
5-PQRSTUVWXYZ[\]^_
6-`abcdefghijklmno
7-pqrstuvwxyz{|}~DEL
8-+00+01+02+03+04+05+06+07+08+09+0A+0B+0C+0D+0E+0F
9-+10+11+12+13+14+15+16+17+18+19+1A+1B+1C+1D+1E+1F
A-+20+21+22+23+24+25+26+27+28+29+2A+2B+2C+2D+2E+2F
B-+30+31+32+33+34+35+36+37+38+39+3A+3B+3C+3D+3E+3F
C-00000040008000C001000140018001C002000240028002C003000340038003C0
D-04000440048004C005000540058005C006000640068006C007000740078007C0
E-0000100020003000400050006000700080009000A000B000C000D000E000F000
F-00004000080000C0000100000444555566XX
-0-1-2-3-4-5-6-7-8-9-A-B-C-D-E-F

In three-byte sequences the continuation bytes' values are shifted left by six bits, or multiplied by 64:

-0-1-2-3-4-5-6-7-8-9-A-B-C-D-E-F
8-+000+040+080+0C0+100+140+180+1C0+200+240+280+2C0+300+340+380+3C0
9-+400+440+480+4C0+500+540+580+5C0+600+640+680+6C0+700+740+780+7C0
A-+800+840+880+8C0+900+940+980+9C0+A00+A40+A80+AC0+B00+B40+B80+BC0
B-+C00+C40+C80+CC0+D00+D40+D80+DC0+E00+E40+E80+EC0+F00+F40+F80+FC0

And in four-byte sequences they're shifted again:

-0-1-2-3-4-5-6-7-8-9-A-B-C-D-E-F
8-+00···+01···+02···+03···+04···+05···+06···+07···+08···+09···+0A···+0B···+0C···+0D···+0E···+0F···
9-+10···+11···+12···+13···+14···+15···+16···+17···+18···+19···+1A···+1B···+1C···+1D···+1E···+1F···
10-+20···+21···+22···+23···+24···+25···+26···+27···+28···+29···+2A···+2B···+2C···+2D···+2E···+2F···
11-+30···+31···+32···+33···+34···+35···+36···+37···+38···+39···+3A···+3B···+3C···+3D···+3E···+3F···

Created 2022-09-14. Index.