As character names:

U+2599 QUADRANT UPPER LEFT AND LOWER LEFT AND LOWER RIGHT character (▙)

As raw characters:

▙

As a string of HTML entities:

▙

Decoder output:

Byte number 1 is decimal 226, hex 0xE2, octal \342, binary 11100010
This is the first byte of a 3 byte sequence.

Byte number 2 is decimal 150, hex 0x96, octal \226, binary 10010110
This is continuation byte 1, expecting 1 more.

Byte number 3 is decimal 153, hex 0x99, octal \231, binary 10011001
This is continuation byte 2, expecting 0 more.

U+2599	QUADRANT UPPER LEFT AND LOWER LEFT AND LOWER RIGHT