no, these are the first 20 triangle numbers:
1 3 6 10 15 21 28 36 45 55
66 78 91 105 120 136 153 171 190 210
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45
36 is a triangle number (1+2+3+4+5+6+8+9), a square (6*6) and an even number.
If all three sides are 9 inches in length, then it is an EQUILATERAL Triangle. All the angles are 60 degrees.
Can 9, 8, and 17 for a triangle?
9