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A241451
Number of partitions p of n such that the number of parts having multiplicity 1 is a part or max(p) - min(p) is a part.
5
0, 1, 0, 1, 1, 4, 6, 9, 13, 21, 28, 35, 52, 68, 89, 121, 155, 205, 264, 340, 433, 555, 693, 872, 1095, 1367, 1695, 2107, 2580, 3180, 3911, 4773, 5803, 7083, 8565, 10364, 12515, 15077, 18075, 21721, 25936, 31023, 36954, 43984, 52152, 61966, 73238, 86586
OFFSET
0,6
FORMULA
a(n) + A241450(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 6 partitions: 42, 411, 321, 3111, 2211, 21111.
MATHEMATICA
z = 30; f[n_] := f[n] = IntegerPartitions[n]; u[p_] := Length[DeleteDuplicates[Select[p, Count[p, #] == 1 &]]]; d[p_] := Length[DeleteDuplicates[p]];
Table[Count[f[n], p_ /; MemberQ[p, u[p]] && MemberQ[p, Max[p]-Min[p]]], {n, 0, z}] (* A241447 *)
Table[Count[f[n], p_ /; ! MemberQ[p, u[p]] && MemberQ[p, Max[p]-Min[p]] ], {n, 0, z}] (* A241448 *)
Table[Count[f[n], p_ /; MemberQ[p, u[p]] && ! MemberQ[p, Max[p]-Min[p]] ], {n, 0, z}] (* A241449 *)
Table[Count[f[n], p_ /; ! MemberQ[p, u[p]] && ! MemberQ[p, Max[p]-Min[p]] ], {n, 0, z}] (* A241450 *)
Table[Count[f[n], p_ /; MemberQ[p, u[p]] || MemberQ[p, Max[p]-Min[p]] ], {n, 0, z}] (* A241451 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 23 2014
STATUS
approved