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%I #9 Apr 12 2019 15:35:08
%S 0,0,0,0,0,1,2,5,10,18,30,49,75,112,163,231,322,441,595,792,1045,1361,
%T 1760,2255,2871,3626,4559,5691,7077,8750,10780,13216,16156,19662,
%U 23868,28866,34828,41882,50262,60138
%N a(n) = A000094(n+4) - A006918(n).
%C Also the number of integer partitions of n - 3 with Durfee square of length > 2, i.e., those with at least 3 parts > 2. The Heinz numbers of these partitions are given by A307515. - _Gus Wiseman_, Apr 12 2019
%p A084845 := proc(n)
%p A000094(n+4)-A006918(n)
%p end proc:
%p seq(A084845(n),n=1..40) ; # _R. J. Mathar_, May 17 2016
%t durf[ptn_]:=Length[Select[Range[Length[ptn]],ptn[[#]]>=#&]];
%t Table[Length[Select[IntegerPartitions[n],durf[#]>2&]],{n,0,30}] (* _Gus Wiseman_, Apr 12 2019 *)
%Y Cf. A000094, A006918, A096771, A115720, A257990, A307515, A325164, A325192.
%K nonn
%O 1,7
%A _Jon Perry_, Jul 12 2003