Jud's sequences

[N. J. A. Sloane]

They are very nice, but they are not well-defined,
for the following technical reason: when I extend
an existing sequence myself, i don't usually make
any record of this.  and this happens all the time.
So the fact that say 6407 is not at present in the database
doesn't mean it won't be there next week.  And of course
it is implicitly present, as a term in A000027.

So i will not be including them.

On the other hand, the following sequence, of a similar
nature, and which Jud contributed to, is (at least for
the first ___ terms) well-defined:

%I A031135
%S A031135 1,2,1,0,2,3,0,6,8,4,63,1,316,42,16,2048,7652,13781,8,24000,11977,
%T A031135 458561,152116956851941670912,1054535,53,26,27,59,4806078,3,35792568,3010349,
%U A031135 2387010102192469724605148123694256128,2,0,53
%N A031135 Diagonal sequence: a(n) = n-th term of sequence An.
%D A031135 E. M. Rains and N. J. A. Sloane, On Cayley's Enumeration of Alkanes (or 4-Valent Trees), J. Integer Sequences, Vol. 2 (1999), Article 99.1.1.
%D A031135 N. J. A. Sloane, My favorite integer sequences, in Sequences and their Applications (Proceedings of SETA '98), C. Ding, T. Helleseth and H. Niederreiter (editors), Springer-Verlag, London, 1999, pp. 103-130.
%H A031135 <a href="http://www.research.att.com/~njas/sequences/JIS/index.html#P99.1.1">Rains-Sloane paper.</a>
%H A031135 <A HREF="http://www.research.att.com/~njas/doc/sg.pdf">My favorite integer sequences</a>
%Y A031135 Cf. A031214, A037181, A051070, A000001, A000002, A000003, A000004, A000005, etc.
%K A031135 nonn
%O A031135 1,2
%A A031135 Proposed by several people, including Jeff Burch (jmburch at osprey.smcm.edu)
%E A031135 Corrected and extended by Jud McCranie (jud.mccranie at mindspring.com). Further extended by njas and emr Dec 8 1998.

[the references refer to the 22nd term, which took over 100 years to compute]

njas