diff --git a/tech/pascals_triangle.wiki b/tech/pascals_triangle.wiki
index 1d81ebc..d7930b9 100644
--- a/tech/pascals_triangle.wiki
+++ b/tech/pascals_triangle.wiki
@@ -18,4 +18,11 @@ can be calculated via
 * The sum of the square of the elements of row `n` is equal to the middle
   element of row `2n`
 * For some row `n` where `n` is prime, all terms in that row except for the 1s
-  are multiples of `p`
+  are multiples of `n`
+* To count odd terms in a row `n`, convert `n` to binary. Let `x` be the number
+  of 1s in the binary value (popcnt) Then the number of odd terms will be `2^x`
+  These values are known as [[goulds_sequence]]
+* Every entry in row `2^(n-1) for n>=0` is odd.
+* Diagonals along left and right edges contain only 1s
+* Diagonals next to the edge of the diagonals count upward
+* Next diagonal inward contains the [[triagnular_numbers]]
diff --git a/tech/triagnular_numbers.wiki b/tech/triagnular_numbers.wiki
new file mode 100644
index 0000000..7f8ba47
--- /dev/null
+++ b/tech/triagnular_numbers.wiki
@@ -0,0 +1,12 @@
+= Triangular Numbers =
+
+Triangular numbers are the number of objects arranged in an equilateral
+triangle.
+
+The first few are
+
+{{{
+0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120, 136, 153, 171,
+190, 210, 231, 253, 276, 300, 325, 351, 378, 406, 435, 465, 496, 528, 561, 595,
+630, 666...
+  }}}