What is the next number in the sequence 1 121 12321 1234321

123454321

Step-by-step explanation:

The given sequence :

We can note that this is a symmetric sequence i.e. the digits in the numbers of the sequence are symmetric .

In the first number there is 2 in the middle and 1 is symmetric.

In the second number there is 3 in the middle and 1 and 2 are symmetric.

Similarly In the third number there is 4 in the middle and 1,2 and 3 are symmetric.

Then in the next number there must be 5 in the middle and 1,2,3,4 must be symmetric.

Hence, the next number must be 123454321

i you goofed up when writing this, because hnot is not a word minusf is not either. i cannot answer   because of that.

step-by-step explanation: