Scan down through this list and notice the special relationships between numbers and their triangles.
Triangle Numbers are simply the sum of all the numbers that preceed a number. For example, the triangle of 5 is 1+2+3+4+5=15. Triangles of numbers have a special relationship to their source numbers so in the case for number 5, 15 has a special relationship to number 5. Since 153 is the triangle of 17 then 153 has a special relationship to 17.
| 1 | 1 |
| 2 | 3 |
| 3 | 6 |
| 4 | 10 |
| 5 | 15 |
| 6 | 21 |
| 7 | 28 |
| 8 | 36 |
| 9 | 45 |
| 10 | 55 |
| 11 | 66 |
| 12 | 78 |
| 13 | 91 |
| 14 | 105 |
| 15 | 120 |
| 16 | 136 |
| 17 | 153 |
| 18 | 171 |
| 19 | 190 |
| 20 | 210 |
| 21 | 231 |
| 22 | 253 |
| 23 | 276 |
| 24 | 300 |
| 25 | 325 |
| 26 | 351 |
| 27 | 378 |
| 28 | 406 |
| 29 | 435 |
| 30 | 465 |
| 31 | 496 |
| 32 | 528 |
| 33 | 561 |
| 34 | 595 |
| 35 | 630 |
| 36 | 666 |
| 37 | 703 |
| 38 | 741 |
| 39 | 780 |
| 40 | 820 |
| 41 | 861 |
| 42 | 903 |
| 43 | 946 |
| 44 | 990 |
| 45 | 1035 |
| 46 | 1081 |
| 47 | 1128 |
| 48 | 1176 |
| 49 | 1225 |
| 50 | 1275 |
| 51 | 1326 |
| 52 | 1378 |
| 53 | 1431 |
| 54 | 1485 |
| 55 | 1540 |
| 56 | 1596 |
| 57 | 1653 |
| 58 | 1711 |
| 59 | 1770 |
| 60 | 1830 |
| 61 | 1891 |
| 62 | 1953 |
| 63 | 2016 |
| 64 | 2080 |
| 65 | 2145 |
| 66 | 2211 |
| 67 | 2278 |
| 68 | 2346 |
| 69 | 2415 |
| 70 | 2485 |
| 71 | 2556 |
| 72 | 2628 |
| 73 | 2701 |
| 74 | 2775 |
| 75 | 2850 |
| 76 | 2926 |
| 77 | 3003 |
| 78 | 3081 |
| 79 | 3160 |
| 80 | 3240 |
| 81 | 3321 |
| 82 | 3403 |
| 83 | 3486 |
| 84 | 3570 |
| 85 | 3655 |
| 86 | 3741 |
| 87 | 3828 |
| 88 | 3916 |
| 89 | 4005 |
| 90 | 4095 |
| 91 | 4186 |
| 92 | 4278 |
| 93 | 4371 |
| 94 | 4465 |
| 95 | 4560 |
| 96 | 4656 |
| 97 | 4753 |
| 98 | 4851 |
| 99 | 4950 |
| 100 | 5050 |