diff --git a/src/strang.jl b/src/strang.jl
index 4f5f1fa..228e9f8 100644
--- a/src/strang.jl
+++ b/src/strang.jl
@@ -46,7 +46,7 @@ LinearAlgebra.isposdef(s::Strang) = true
     @boundscheck checkbounds(A, i, j)
     if i == j
         return T(2)
-    elseif i == j + 1 || i == j - 1
+    elseif abs(i-j) == 1
         return -one(T)
     else
         return zero(T)
diff --git a/test/strang.jl b/test/strang.jl
index eac28c8..fac7525 100644
--- a/test/strang.jl
+++ b/test/strang.jl
@@ -15,6 +15,12 @@ using Test: @test, @testset, @test_throws, @inferred
     @test A isa Strang{Int16}
     @test A == diagm(0 => 2ones(n), 1 => -ones(n-1), -1 => -ones(n-1))
 
+    @test (@inferred getindex(A, 1, 2)) == -1
+    @test A[begin] == 2
+    @test A[end] == 2
+    @test A[1,end] == 0
+
     x = rand(n)
-    @test A * x ≈ Matrix(A) * x
+    y = @inferred *(A, x)
+    @test y ≈ Matrix(A) * x
 end