How Do We Correctly Calculate the Distribution of Bosons Among Energy Levels?

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I want to calculate the number of ways for putting [itex]N_1,N_2,N_3,...,N_i,...[/itex] bosons in energy levels with degeneracies [itex]g_1,g_2,g_3,...,g_i,...[/itex].
The particles are indistinguishable and there can be any number of particles in a state.
The level with degeneracy [itex]g_i[/itex] has [itex]N_i[/itex] particles in it.The first of this [itex]N_i[/itex] particles has [itex]g_i[/itex] states to choose.The second,again has [itex]g_i[/itex] choices and the same for all of them.So there are [itex]g_i^{N_i}[/itex] ways for putting [itex]N_i[/itex] particles in [itex]g_i[/itex] sates.But the particles are indistinguishable so their order is not important and so [itex]g_i^{N_i}[/itex] reduces to [itex]\frac{g_i^{N_i}}{N_i!}[/itex]. So the number of ways for putting [itex]N_1,N_2,N_3,...,N_i,...[/itex] bosons in energy levels with degeneracies [itex]g_1,g_2,g_3,...,g_i,...[/itex] is:
[itex] \prod_i \frac{g_i^{N_i}}{N_i!}[/itex]

But the above result will give us sth like Boltzmann distribution,not Bose-Einstein's and we know that the answer should be like below:
[itex] \prod_i \frac{(N_i+g_i-1)!}{N_i!(g_i-1)!}[/itex]

But what is wrong?
In deriving my formula,I assumed only that the particles are indistinguishable and don't follow Pauli's principle,the same assumptions made for bosons.So what was different?
Thanks
 
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Dividing by N_i! you are overcounting states. Take just one state with degeneracy g_1=1 and two bosons.
Obviously dividing by 2! is not correct.