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A241342
Number of partitions p of n such that floor(mean(p)) is a part and ceiling(mean(p)) is not.
5
0, 0, 0, 0, 0, 1, 1, 3, 4, 6, 9, 16, 11, 29, 36, 38, 51, 89, 81, 145, 134, 191, 278, 369, 290, 520, 678, 768, 875, 1320, 1161, 1961, 2009, 2624, 3453, 3733, 3650, 6131, 7244, 8187, 8097, 12563, 12301, 17770, 18725, 20962, 29260, 34902, 31199, 46507, 50889
OFFSET
0,8
EXAMPLE
a(10) counts these 9 partitions: 631, 6211, 532, 5221, 511111, 4222, 4111111, 331111, 31111111.
MATHEMATICA
z = 30; f[n_] := f[n] = IntegerPartitions[n];
t1 = Table[Count[f[n], p_ /; MemberQ[p, Floor[Mean[p]]] && MemberQ[p, Ceiling[Mean[p]]]], {n, 0, z}] (* A241340 *)
t2 = Table[Count[f[n], p_ /; ! MemberQ[p, Floor[Mean[p]]] && MemberQ[p, Ceiling[Mean[p]]]], {n, 0, z}] (* A241341 *)
t3 = Table[Count[f[n], p_ /; MemberQ[p, Floor[Mean[p]]] && ! MemberQ[p, Ceiling[Mean[p]]]], {n, 0, z}] (* A241342 *)
t4 = Table[Count[f[n], p_ /; ! MemberQ[p, Floor[Mean[p]]] && ! MemberQ[p, Ceiling[Mean[p]]]], {n, 0, z}] (* A241343 *)
t5 = Table[Count[f[n], p_ /; MemberQ[p, Floor[Mean[p]]] || MemberQ[p, Ceiling[Mean[p]]]], {n, 0, z}] (* A241344 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 20 2014
STATUS
approved