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A206556
Number of 6's in the last section of the set of partitions of n.
2
0, 0, 0, 0, 0, 1, 0, 1, 1, 2, 2, 5, 4, 8, 9, 14, 16, 26, 28, 42, 50, 69, 82, 114, 133, 179, 215, 279, 335, 434, 516, 657, 789, 987, 1182, 1473, 1754, 2164, 2583, 3154, 3755, 4567, 5414, 6542, 7753, 9307, 11000, 13158, 15501, 18456, 21712, 25731, 30196, 35677
OFFSET
1,10
COMMENTS
Zero together with the first differences of A024790. Also number of occurrences of 6 in all partitions of n that do not contain 1 as a part. For the definition of "last section of n" see A135010. It appears that the sums of six successive terms give the partition numbers A000041.
FORMULA
It appears that A000041(n) = Sum_{j=1..6} a(n+j), n >= 0.
PROG
(Sage) A206556 = lambda n: sum(list(p).count(6) for p in Partitions(n) if 1 not in p)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Feb 09 2012
STATUS
approved