%I #23 Dec 01 2013 13:35:02
%S 0,0,0,0,0,0,1,0,1,1,2,2,4,5,7,9,13,16,23,28,39,48,64,79,104,128,165,
%T 204,258,317,399,487,606,739,912,1105,1356,1637,1994,2400,2906,3485,
%U 4199,5016,6015,7164,8553,10151,12076,14286,16930,19974,23588,27749
%N Number of 7's in the last section of the set of partitions of n.
%C Zero together with the first differences of A024791. Also number of occurrences of 7 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 seven successive terms give the partition numbers A000041.
%F It appears that A000041(n) = Sum_{j=1..7} a(n+j), n >= 0.
%o (Sage) A206557 = lambda n: sum(list(p).count(7) for p in Partitions(n) if 1 not in p)
%Y Column 7 of A182703 and of A194812.
%Y Cf. A000041, A135010, A138121, A182712-A182714, A206555, A206556, A206558-A206560.
%K nonn
%O 1,11
%A _Omar E. Pol_, Feb 09 2012
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