#!/usr/bin/python3
# Řešení 32-2-5, napsal Martin Medvěd Mareš

N, K = map(int, input().split())

S = N*(N+1)//2
if abs(K) > S or K%2 != S%2:
    print("Nelze.")
else:
    out = []
    for x in range(N, 0, -1):
        if K >= 0:
            y = x
        else:
            y = -x
        out.append(y)
        K -= y
    print(*out)