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A240179
Number of partitions of n such that (least part) <= (multiplicity of greatest part).
6
0, 1, 1, 2, 4, 5, 8, 11, 17, 23, 33, 43, 61, 79, 108, 140, 187, 238, 314, 397, 513, 648, 826, 1032, 1307, 1622, 2029, 2508, 3113, 3821, 4713, 5754, 7048, 8569, 10431, 12618, 15290, 18413, 22193, 26628, 31954, 38184, 45639, 54340, 64694, 76780, 91077, 107732
OFFSET
0,4
COMMENTS
Also, for n >= 0, a(n) is the number of partitions of n such that (greatest part) >= (multiplicity of least part). For n >=1, a(n) is also the number of partitions of n such that (least part) >= (multiplicity of greatest part), as well as the number of partitions p of n such that min(p) = min(c(p)), where c = conjugate..
FORMULA
a(n) = A240178(n) + A240180(n), for n >= 0.
2*a(n) + A240180(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 8 partitions: 51, 411, 321, 3111, 222, 2211, 21111, 111111.
MATHEMATICA
z = 60; f[n_] := f[n] = IntegerPartitions[n];
Table[Count[f[n], p_ /; Min[p] < Count[p, Max[p]]], {n, 0, z}] (* A240178 *)
Table[Count[f[n], p_ /; Min[p] <= Count[p, Max[p]]], {n, 0, z}] (* A240179 *)
Table[Count[f[n], p_ /; Min[p] == Count[p, Max[p]]], {n, 0, z}] (* A240180 *)
Table[Count[f[n], p_ /; Min[p] > Count[p, Max[p]]], {n, 0, z}] (* A240178, n>0 *)
Table[Count[f[n], p_ /; Min[p] >= Count[p, Max[p]]], {n, 0, z}] (* A240179, n>0 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 02 2014
STATUS
approved