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# M-numbers

In 1995 *The Encyclopedia of Integer Sequences* was published, containing 5488 sequences in lexicographic order and assigned **M-numbers** from M0000 to M5487.

The rules requiring sequences to consist of nonnegative integers and to be infinite (or conjectured to be, e.g. A000668, the Mersenne primes) remain in place. The initial 0's and 1's are now preserved, but the first nontrivial term (i.e. exceeding 1) in the sequence must be between 2 and 999, except for the 4 sequences of 0's and 1's M0000 to M0003. The artificial sequences M0004 and M5487 mark the boundaries of the table.

The *Encyclopedia* includes the references to the corresponding sequences (which may differ in their few initial terms) in *A Handbook of Integer Sequences* as N-numbers from N0001 to N2372 (instead of 1 to 2372.) The *Encyclopedia* includes the A-numbers (absolute numbers) that are used in the OEIS, whereas the *Handbook* did not.