import type { Numeric } from '../types/index';
/**
 * * Generates the first `limit` Fibonacci numbers.
 *
 * @param limit The number of Fibonacci numbers to generate.
 * @returns An array containing the first `limit` Fibonacci numbers.
 */
export declare function getFibonacciSeries(limit: Numeric): number[];
/**
 * * Generates the first `limit` Fibonacci numbers using recursion with memoization.
 *
 * @param limit - The number of Fibonacci numbers to generate.
 * @returns An array containing the first `limit` Fibonacci numbers.
 */
export declare function getFibonacciSeriesMemo(limit: Numeric): number[];
/**
 * * Generator function for Fibonacci sequence up to a given limit.
 *
 * @param limit - Number of Fibonacci numbers to generate.
 * @param onYield - Optional callback triggered on each yield with the current value and index.
 * @returns A generator yielding Fibonacci numbers one by one.
 */
export declare function fibonacciGenerator(limit: Numeric, onYield?: (value: number, index: number) => void): Generator<number, void, void>;
/**
 * * Calculates the `n`th Fibonacci number using optimized space.
 *
 * @param index - The index (0-based) of the Fibonacci number.
 * @returns The index=`n`th Fibonacci number.
 */
export declare function getNthFibonacci(index: Numeric): number;