Try the multiples of the numbers 1-9 and take their cross s…

Try the multiples of the numbers 1-9 and take their cross sum and write them down.
There are quite some interesting patterns.

3, 6 ,9 are interesting.
3: 3, 12, 21, 30, 39, 48, 57, 66, 75, 84, 93, 102, ...cross sum is always 3.
6: 6, 15, 24, 33, 42, 51, 60. 69, 78, 87, 96, 105, ...cross sum is always 6.
9: 9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99, 108, ...cross sum is always 9.

8: 8, 16, 32, 40, 48, 56, 64, 72, 80, 88, 96, 104, 112,...
Cross sum: 8, 7,6, 5, 4, 3, 2, 1, 9,8, 7, 6, 5, 4, 3, 2, 1, 9, ...Its a reapeating countdown.

5: Cross sum of multiples of five is counting up, but with two entangled counts.

7: It is kinda random but is repetitive as well.
The pattern is: 753186429

For the number two the pattern is: 246813579

For the number four the pattern is: 483726159

The cross sum of the numbers 1-9 is 54, which is 9 again.