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Number of partitions p of n such that floor(n/2) is not a part of p.
1

%I #8 Mar 02 2014 23:05:52

%S 1,1,1,3,4,8,10,17,23,35,45,66,86,120,154,209,267,355,448,585,736,946,

%T 1178,1498,1857,2335,2875,3583,4389,5428,6611,8118,9846,12013,14498,

%U 17592,21147,25525,30558,36711,43791,52382,62259,74173,87879,104303,123179

%N Number of partitions p of n such that floor(n/2) is not a part of p.

%H Giovanni Resta, <a href="/A238546/b238546.txt">Table of n, a(n) for n = 1..500</a>

%F a(n) + A119620(n+1) = A000041(n), for n>1.

%F a(n) = p(n) - p(ceiling(n/2)) = A000041(n) - A000041(ceiling(n/2)), for n>1. - _Giovanni Resta_, Mar 02 2014

%e a(6) counts all the 11 partitions of 6 except 33, 321, 3111.

%t Table[Count[IntegerPartitions[n], p_ /; !MemberQ[p, Floor[n/2]]], {n, 50}]

%Y Cf. A119620.

%K nonn,easy

%O 1,4

%A _Clark Kimberling_, Feb 28 2014