0b101010101

0b101010101 is a binary literal using the 0b prefix to denote an integer value in base-2. The sequence consists of nine bits arranged as an alternating pattern of 1s and 0s, starting and ending with 1.

In decimal form, this value is 341. This is calculated as 2^8 + 2^6 + 2^4 + 2^2 + 2^0, which sums to 256 + 64 + 16 + 4 + 1. In hexadecimal, the same value is 0x155, since 341 equals 0x155 in base-16.

The bit pattern 101010101 is notable for its regular alternation, containing five 1s and four 0s. As a binary number, it represents an odd integer (due to the least significant bit being 1) and can be used in demonstrations of bitwise operations or pattern recognition in low-level programming contexts.

In programming contexts, the 0b prefix is used in several languages to introduce binary literals. Languages that support this syntax include Python, JavaScript (ECMAScript 6 and later), Java (since Java 7), C++ (since C++14), Rust, and others. Some languages also offer readability features, such as underscores within literals to separate groups of digits, or allow different lengths and alignments depending on the target architecture or language conventions.

Overall, 0b101010101 is a compact example of a binary integer with a simple, repeating structure, useful for illustrating binary notation and basic arithmetic conversions between bases.