MOD = 998244353i64

def inv(v : Int64)
  pow(v, MOD - 2)
end

def pow(v : Int64, p)
  ret = 1i64
  while p > 0
    if (p & 1i64) != 0
      ret *= v
      ret %= MOD
    end
    v *= v
    v %= MOD
    p >>= 1
  end
  ret
end

n64, k = read_line.split.map(&.to_i64)
n = n64.to_i
inv5 = inv(5i64)
inv5_3 = inv5 * 3 % MOD
inv5_4 = inv5 * 4 % MOD
mat = Matrix(Int64).new(n * 4, n * 4)
(n * 4 - 1).times do |i|
  mat.a[i + 1][i] = inv5
  if i % 4 == 0
    mat.a[0][i] = inv5_4
  else
    mat.a[0][i] = inv5_3
    mat.a[1][i] = inv5
  end
end
mat.a[0][n * 4 - 1] = inv5_3
mat.a[1][n * 4 - 1] = inv5
mat = mat.pow(k - 1)
puts mat.a[n * 4 - 1][0] * inv5 % MOD

class Matrix(T)
  @a : Array(Array(T))
  getter :a, :d1, :d2

  def initialize(n : Int32, m : Int32)
    @a = Array.new(n) { Array.new(m, T.zero) }
    @d1 = n
    @d2 = m
  end

  def clone
    ret = Matrix(T).new(@d1, @d2)
    @d1.times do |i|
      @d2.times do |j|
        ret.a[i][j] = @a[i][j]
      end
    end
    return ret
  end

  def [](idx : Int32)
    return @a[idx]
  end

  def mul(other : Matrix(T))
    if @d2 != other.d1
      raise ArgumentError.new
    end
    d3 = other.d2
    tmp = Array.new(d3) { Array.new(@d2, T.zero) }
    d3.times do |i|
      tr1 = tmp[i]
      @d2.times do |j|
        tr1[j] = other[j][i]
      end
    end
    ret = Array.new(@d1) { Array.new(d3, T.zero) }
    @d1.times do |i|
      row1 = @a[i]
      ret1 = ret[i]
      d3.times do |j|
        sum = T.zero
        row2 = tmp[j]
        @d2.times do |k|
          sum += row1[k] * row2[k]
          sum %= MOD
        end
        ret1[j] = sum
      end
    end
    @a = ret
  end

  def mul_l(other : Matrix(T))
    # in-place
    if other.d2 != @d1
      raise ArgumentError.new
    end
    d3 = @d2
    tmp = Array.new(d3) { Array.new(@d1, T.zero) }
    d3.times do |i|
      tr1 = tmp[i]
      @d1.times do |j|
        tr1[j] = @a[j][i]
      end
    end
    other.d1.times do |i|
      row1 = other.a[i]
      ret1 = @a[i]
      d3.times do |j|
        sum = T.zero
        row2 = tmp[j]
        other.d2.times do |k|
          sum += row1[k] * row2[k]
          sum %= MOD
        end
        ret1[j] = sum
      end
    end
  end

  def pow(p : Int64)
    b = Matrix(T).new(@d1, @d2)
    ret = Matrix(T).new(@d1, @d2)
    @d1.times do |i|
      @d2.times do |j|
        b.a[i][j] = @a[i][j] % MOD
      end
      ret.a[i][i] = 1
    end
    while p > 0
      if (p & 1) != 0
        ret.mul_l(b)
      end
      b.mul(b)
      p >>= 1
    end
    return ret
  end
end