Using the simplest polynomial of order 4,
Un = (-23n4 + 266n3 - 1033n2 + 1630n - 32)/24, for n = 1, 2, 3, ...
the next number will be 22.
-5
The next number is -21
109 Answered by G.S.Nair
The pattern in the series appears to alternate between adding 3 and multiplying by 3. Starting with 15, we add 3 to get 18, then multiply by 3 to get 54. Next, we add 3 to 54 to get 57, and then multiply by 3 to reach 171. Following this pattern, the next step is to add 3 to 171, which gives us 174. Thus, the next number in the series is 174.
26
The series seems to be "add 3," so the next number in the series would be 12 followed by 15.
15
11
15
The pattern is add three and then multiply by three. The next number is 174.
20
The next time the series is playing is December 15.
-5
The next number is -21
53
109 Answered by G.S.Nair
The series 1 6 10 13 15 (1+5=6; 6+4=10, 10+3=13; 13+2=15) is completed by 15+1=16. The answer is 16.