OFFSET
1,5
COMMENTS
LINKS
EXAMPLE
For n = 7 the last shell of 7 contains four regions: [3],[5,2],[4],[7,3,2,2,1,1,1,1,1,1,1,1,1,1,1] so we have:
----------------------------------------------------------
. Largest Number
Region part of parts Rank
----------------------------------------------------------
. 1 3 1 2
. 2 5 2 3
. 3 4 1 3
. 4 7 15 -8
.
The sum of positive ranks is a(7) = 2 + 3 + 3 = 8.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Omar E. Pol, Apr 29 2012
STATUS
approved