diff --git a/src/d2s_small_table.rs b/src/d2s_small_table.rs
index 08519a2..9c23304 100644
--- a/src/d2s_small_table.rs
+++ b/src/d2s_small_table.rs
@@ -112,7 +112,7 @@ pub unsafe fn compute_pow5(i: u32) -> (u64, u64) {
     let b0 = m as u128 * mul.0 as u128;
     let b2 = m as u128 * mul.1 as u128;
     let delta = pow5bits(i as i32) - pow5bits(base2 as i32);
-    debug_assert!(base < POW5_OFFSETS.len() as u32);
+    debug_assert!(i / 16 < POW5_OFFSETS.len() as u32);
     let shifted_sum = (b0 >> delta)
         + (b2 << (64 - delta))
         + ((*POW5_OFFSETS.get_unchecked((i / 16) as usize) >> ((i % 16) << 1)) & 3) as u128;
@@ -165,7 +165,7 @@ pub unsafe fn compute_pow5(i: u32) -> (u64, u64) {
     }
     // high1 | sum | low0
     let delta = pow5bits(i as i32) - pow5bits(base2 as i32);
-    debug_assert!(base < POW5_OFFSETS.len() as u32);
+    debug_assert!(i / 16 < POW5_OFFSETS.len() as u32);
     (
         shiftright128(low0, sum, delta as u32)
             + ((*POW5_OFFSETS.get_unchecked((i / 16) as usize) >> ((i % 16) << 1)) & 3) as u64,