export declare const ONE: bigint;
/**
 * Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
 * @remarks
 * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
 */
export declare function exp(x: bigint): bigint;
/**
 * Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
 */
export declare function ln(a: bigint): bigint;