Ok, lets try this.
Write the numbers 0 to 59 in a line.
Next line put an X under the first number in the combination, 0.
The next two numbers 1 & 2 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 1.
0,2 &3 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 2.
0, 1, 3 & 4 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 3.
1, 2, 4, & 5 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 4.
2, 3, 5 & 6 are NOT three away so put X's under those also.
Continue doing that till the last four lines are
Next line put an X under the next first number in the combination, 56.
54, 55, 57, & 58 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 57.
55, 56, 58 & 59 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 58.
56, 57, & 59 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 59.
57 & 58 are NOT three away so put X's under those also.
Now you have accounted for every first number in the combination.
The squares without X's are under the possible second numbers in the combinations. Count them and multiply by 60 for the third number.
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Gene
Write the numbers 0 to 59 in a line.
Next line put an X under the first number in the combination, 0.
The next two numbers 1 & 2 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 1.
0,2 &3 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 2.
0, 1, 3 & 4 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 3.
1, 2, 4, & 5 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 4.
2, 3, 5 & 6 are NOT three away so put X's under those also.
Continue doing that till the last four lines are
Next line put an X under the next first number in the combination, 56.
54, 55, 57, & 58 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 57.
55, 56, 58 & 59 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 58.
56, 57, & 59 are NOT three away so put X's under those also.
Next line put an X under the next first number in the combination, 59.
57 & 58 are NOT three away so put X's under those also.
Now you have accounted for every first number in the combination.
The squares without X's are under the possible second numbers in the combinations. Count them and multiply by 60 for the third number.
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Gene