Formula for the nth Triangular Number:
t(n) = 1/2n(n + 1) OR t(n) = (n2 + n)/2
t(0) = 0
t(1) = 1
t(2) = 3
t(3) = 6
t(4) = 10
t(5) = 15
t(6) = 21
t(7) = 28
t(8) = 36
t(9) = 45
t(10) = 55
t(11) = 66
t(12) = 78
t(13) = 91
t(14) = 104
t(15) = 120
For a more extensive list, or for more any more information about the Triangular Numbers, type "Triangular Numbers" into Google. You'll find lots of helpful websites there.
1, 3, 6, 10, 15, 21, 28, 36
1,3,6,10,15,21,28,36,45,47,66,78,91,95
0,1,3,6,10,15,21,28,36,45,56,68,81,95,110,126,143,161,180,200. That's all the triangular numbers up to 200! I hope that's helped anyone with any thing.
45
None of the factor pairs of 120 add up to -14. If that was -120, you could use -20 and 6.
0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120, 136, 153
1, 3, 6, 10, 15, 21, 28, 36
1,3,6,10,15,21,28,36,45,47,66,78,91,95
0,1,3,6,10,15,21,28,36,45,56,68,81,95,110,126,143,161,180,200. That's all the triangular numbers up to 200! I hope that's helped anyone with any thing.
45
1'3'10 etc;
1 2.56 4 9 10.24 16 25 36 40.96 49 64 81 100 110.25
28 and 10 are both triangular numbers and add up to 38
None of the factor pairs of 120 add up to -14. If that was -120, you could use -20 and 6.
-15+-8=-23 -15*-8=120
How about: 120+1.2 = 121.2
1,4,9,16,25,36,49,64,81,100,121,144,169,196,225,256,289,324,361,400 All the square numbers up to 20!