using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        Dictionary<int, double[]> counts1 = new Dictionary<int,double[]>

        {

            { 1, [27.1879476277225, 37.5134291710464, 73.6017562082174, 93.0498965871104, 90.6893190757005, 181.946376092798] },

            { 2, [27.1879476277225, 37.5134291710464, 73.6017562082174, 93.0498965871104, 90.6893190757005, 181.946376092798] },

            { 3, [-25, 54, -52, 25, 104, 48] },

        };

        var duplicateKeys = counts1.GroupBy(x => x.Value, new ArrayEqualityComparer<double>()).Where(x => x.Count()> 1).SelectMany(g => g).Select(i => i.Key);

        var keysToRemove = counts1.Keys.Except(duplicateKeys).ToList();

        foreach (int key in keysToRemove)

        {

            counts1.Remove(key);

        }

        foreach (var pair in counts1)

        {

            Console.WriteLine("{0}: [{1}]", pair.Key, string.Join(", ", pair.Value));

        }

    }

}

​

public sealed class ArrayEqualityComparer<T> : IEqualityComparer<T[]>

{

    private readonly IEqualityComparer<T> _elementComparer;

    public ArrayEqualityComparer(IEqualityComparer<T> elementComparer)

    {

        _elementComparer = elementComparer ?? throw new ArgumentNullException(nameof(elementComparer));

    }

    public ArrayEqualityComparer()

    {

        _elementComparer = EqualityComparer<T>.Default;

    }

    public int GetHashCode(T[] obj)

    {

        if (obj is null || obj.Length == 0) return 0;

        HashCode code = new HashCode();

        for (int index = 0; index < obj.Length; index++)

        {

            T element = obj[index];

            code.Add(element, _elementComparer);

        }

        return code.ToHashCode();

    }

    public bool Equals(T[] x, T[] y)

    {

        if (x is null) return y is null;

        if (y is null) return false;

        if (x.Length != y.Length) return false;

        for (int index = 0; index < x.Length; index++)

        {

            T xElement = x[index];

            T yElement = y[index];

            if (!_elementComparer.Equals(xElement, yElement))

            {

                return false;

            }

        }

        return true;

    }

}