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A241826
Number of partitions p = [x(1), ..., x(k)], where x(1) >= x(2) >= ... >= x(k), of n such that min(x(i) - x(i-1)) >= number of distinct parts of p.
6
1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 7, 7, 9, 10, 12, 13, 16, 17, 20, 22, 25, 27, 31, 33, 37, 40, 45, 48, 54, 58, 65, 70, 78, 84, 94, 101, 112, 121, 134, 144, 159, 171, 188, 202, 221, 237, 259, 277, 301, 322, 349, 372, 402, 429, 462, 492, 529, 563, 605, 643
OFFSET
0,5
COMMENTS
For the partition [n] of n, "min(x(i) - x(i-1))" is (as in the Mathematica program) interpreted as n.
FORMULA
a(n) = A241825(n) + A241827(n).
a(n) + A241823(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 3 partitions: 6, 51, 42.
MATHEMATICA
z = 30; f[n_] := f[n] = IntegerPartitions[n]; d[p_] := d[p] = Length[DeleteDuplicates[p]]; g1[p_] := Min[-Differences[p]]
Table[Count[f[n], p_ /; g1[p] < d[p]], {n, 0, z}] (* A241823 *)
Table[Count[f[n], p_ /; g1[p] <= d[p]], {n, 0, z}] (* A241824 *)
Table[Count[f[n], p_ /; g1[p] == d[p]], {n, 0, z}] (* A241825 *)
Table[Count[f[n], p_ /; g1[p] >= d[p]], {n, 0, z}] (* A241826 *)
Table[Count[f[n], p_ /; g1[p] > d[p]], {n, 0, z}] (* A241827 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 30 2014
STATUS
approved