Value a(6) in doubt for a =

Rainer Rosenthal r.rosenthal at web.de
Mon Jan 14 17:46:09 CET 2008


The values of
http://www.research.att.com/~njas/sequences/A101877
are defined as  a(n) = max(S_n) where the sum of
reciprocals of S_n is n. It is claimed that no S_n
with smaller maximum could be found.

I checked

        ReciprocalSum(S_n) = n

for n=1..6 and it was correct for n=1..5 but incorrect
for n=6:

    ReciprocalSum(S_6) is less than 6 (about 5.76).

I wasn't able to guess what's wrong with S_6 but following
a remark about the inclusion of S_n in S_{n+1} I checked
whether S_5 was a subset of the S_6, given there. An no,
it is not. S_6 lacks {80, 112, 144, 154, 165, 175, 176},
but adding these is not enough.

How to repair the description of A101877 and confirm
a(6) = 469?

Rainer Rosenthal
r.rosenthal at web.de








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