import sys

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines

class BinaryIndexedTree():
    def __init__(self, seq):
        self.size = len(seq)
        self.depth = self.size.bit_length()
        self.build(seq)

    def build(self, seq):
        data = seq
        size = self.size
        for i, x in enumerate(data):
            j = i + (i & (-i))
            if j < size:
                data[j] += data[i]
        self.data = data

    def get_sum(self, i):
        data = self.data
        s = 0
        while i:
            s += data[i]
            i -= i & -i
        return s

    def add(self, i, x):
        data = self.data
        size = self.size
        while i < size:
            data[i] += x
            i += i & -i

N, K, *P = map(int, read().split())

bit = BinaryIndexedTree([0] * (N + 1))
A = []
for x in P:
    bit.add(x, 1)
    A.append(x - bit.get_sum(x))

A = A[::-1]

def g(N, MOD, x):
    # とりあえず愚直実装
    # return sum(i % MOD for i in range(x, x + N))
    ret = -x * (x - 1) // 2
    N += x
    x = 0
    q, r = divmod(N, MOD)
    ret += q * (MOD - 1) * MOD // 2
    ret += r * (r - 1) // 2
    return ret

def f(N, MOD, rep, x, rest):
    # x, x, ..., x, x+1, x+1, ..., x+1, % MOD の和
    # N 項までとる。最初の rest 項は定数。rep 回ずつ。
    ret = 0
    n = min(N, rest)
    N -= n
    ret += x * n
    x = (x + 1) % MOD
    q, r = divmod(N, rep)
    ret += g(q, MOD, x) * rep
    x = (x + q) % MOD
    ret += x * r
    return ret

INF = K + 10
rest = 1
fact = 1
answer = 0
for i, x in enumerate(A):
    answer += f(K, i + 1, fact, x, rest)
    if rest < INF:
        rest += fact * (i - x)
    if fact < INF:
        fact *= (i + 1)

MOD = 10**9 + 7
print(answer % MOD)