Theorem pow2ne0 ≪ | index | src | ≫ 

theorem pow2ne0 (b: nat): $ 2 ^ b != 0 $;
StepHypRefExpression
1 powne0 
2 != 0 -> 2 ^ b != 0
2 d2ne0 
2 != 0
3 1, 2 ax_mp 
2 ^ b != 0

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_11, ax_12), axs_set (elab, ax_8), axs_the (theid, the0), axs_peano (peano1, peano2, peano5, addeq, muleq, add0, addS, mul0, mulS)