[seqfan] Add neighbours, use their digits
Eric Angelini
Eric.Angelini at kntv.be
Sat Nov 2 10:22:01 CET 2013
Hello SeqFans,
this is a nightmare to compute by hand:
S = 1,10,2,19,73,100,3,20,4,39,54,...
Let R be a(n)+a(n+1)
We want R to be written with some (or
all) the digits belonging to a(n) or a(n+1)
or both.
S is extended using the smallest
integer not yet present in S and
not leading to a contradiction.
We see here that 1+10=11 and yes,
the digits of 11 belong to {1,1,0}
Then 10+2=12 and yes, the digits
of 12 belong to {1,0,2}
Then 2+19=21 and yes, the digits
of 21 belong to {2,1,9}
Then 19+73=91 and yes, etc.
I have absolutely no idea on how
to extend S. But I know that S is
infinite (because the trick 73+100=173 will work for ever).
Does someone have the patience
to check and extend S?
(my 6th term, "100", might be wrong).
Best,
É.
Propulsé d'un aPhone
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