Find the wrong number in the following number series. 100 140 216 340 525 780

The pattern is n² - n for n = 10, 12, 15, 19, 23, 28: 100 (10²-10), 140 (12²-4), 216 (15²-15), 340 (19²-21), 525, 780 (28²-4). The pattern breaks at 525. For n=23, the correct term should be 23² - 23 = 529 - 23 = 506, not 525. Alternatively, looking at the pattern of subtracting n, the sequence 10, 4, 15, 21, ?, 4 is inconsistent. Another valid pattern: differences between consecutive terms increase by consecutive odd numbers starting from 9: 140-100=40, 216-140=76 (40+36), 340-216=124 (76+48), next should be 124+61=185, giving 525, then 185+70=255, giving 780. However, checking 460 from another series suggests the odd number increments should be 36, 48, 60, 72, 84, making 525 incorrect.