[seqfan] Subset

John W. Nicholson reddwarf2956 at yahoo.com
Fri Nov 22 12:59:57 CET 2013

I would like to see a search keyword called "subset:" which allows you to search an A-sequence for any other A-sequence subset. For example, "subset:A002386" would result in A205827, A111870, A182514, and other A-sequences which are subsets to A002386. It would not only use the A-sequence "list" values, but also b-file sequence values during a search.

The reason I ask of this happening is because of the need to see if any of the subsets can be extended using the values of the set. With the examples above we can see that if A205827 is extended with A002386 values and related values, like A000101=Nextprime(A002386), A005669 = pi(A002386), we can see A111870 and A182514 can be extended also in the same manner but use A002386 as the superset.

I realize that some sets (natural numbers) will not work well for this and an error can be used as to shorten the search with those as to say "Sorry, you are asking to for much. Please pick a smaller subset" . Even using A000040 may be to much, so maybe make it "primesubset:"

John W. Nicholson

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