The book and programs are not oracles, and cannot perform miracles. For example, if we submit the following sequence, which simply counts the number of terms in a particular arrangement of a perturbation solution of a heat transfer problem (we would like to know how quickly the size of the solution is growing),
we get no answer.
Other failures can of course occur. The following example shows what
might happen, and the potential for mis-identification of a sequence.
If we
submit the sequence [0, 1, 2, 3, 5, 7, 9, 12, 15, 18] to superseeker, it
returns matches for both M0638 and for M0639, which agree to the first 10
entries. The 11th entry for M0638 is 22, whilst the 11th entry for M0639 is 23.
One of them must be wrong, and this brings home the fact that even if the
programs or book say that the sequence you give it is X only, that might
just be a numerical coincidence.
The user of the book and programs must remember that a match does not prove that the sequence found is the one you are looking for, and it is up to the user to demonstrate that any matches found by the programs or in the book are really appropriate for the problem at hand.