0o1231

0o1231 is an octal numeric literal used in several programming languages to denote an integer in base-8. The prefix 0o signals that the digits that follow are octal digits (0 through 7). In decimal, 0o1231 equals 665.

In Python, the 0o prefix was introduced in Python 3 to distinguish octal literals from decimal numbers, replacing the older style that used a leading zero. Therefore, 0o1231 in Python 3 represents the integer 665. Other languages also adopt the 0o prefix for octal notation, such as JavaScript (ES6/ES2015 and later) and Rust, among others. The 0o prefix improves readability and reduces confusion with decimal and hexadecimal representations.

Numerical conversion: 0o1231 equals 1×8^3 + 2×8^2 + 3×8^1 + 1×8^0 = 512 + 128 + 24 + 1 = 665. In practice, octal literals are often used to express bit or permission patterns in a compact form, though 0o1231 specifically is a generic example value rather than a standard permission set.

Caveats: Digits must be in the range 0–7. Including digits outside that range (such as 8 or 9) would produce a syntax error in languages that support 0o octal literals. Some languages treat leading zeros differently or have additional features like underscores for readability (for example, Python allows 0o1_231). Overall, 0o1231 serves as a representative octal literal illustrating how base-8 notation is commonly expressed in modern programming contexts.