You want to fill in these blanks. There are many ways.
__, __, __, __, 42, __, __, __, __, __.
Pick any number, and subtract it over and over to get the 4 numbers
left of 42, and add it over and over to get the 5 numbers to the
right of 42.
If you choose 1, the sequence would be
38, 39, 40, 41, 42, 43, 44, 45, 46, 47.
If you choose 2, the sequence would be
34, 36, 38, 40, 42, 44, 46, 48, 50, 53.
If you choose 3, the sequence would be
30, 33, 36, 39, 42, 45, 48, 51, 54, 57.
If you choose 10, the sequence would be
2, 12, 22, 32, 42, 52, 62, 72, 82, 92.
If you choose -29, the sequence would be
158, 129, 100, 71, 42, 13, -16, -45, -74, -103.
Choose any of those or whatever you favorite number is.
You could even choose 0 and the sequence would be:
42, 42, 42, 42, 42, 42, 42, 42, 42, 42.
That's a funny one but a sequence nevertheless. :)
Edwin