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A241821
Number of partitions p = [x(1), ..., x(k)], where x(1) >= x(2) >= ... >= x(k), of n such that max(x(i) - x(i-1)) >= number of distinct parts of p.
6
0, 0, 0, 0, 1, 2, 4, 6, 10, 13, 22, 29, 40, 55, 76, 95, 129, 167, 215, 278, 354, 448, 570, 716, 896, 1115, 1387, 1713, 2116, 2597, 3182, 3881, 4741, 5748, 6976, 8416, 10177, 12219, 14704, 17592, 21051, 25101, 29960, 35559, 42267, 50017, 59253, 69898, 82524
OFFSET
0,6
FORMULA
a(n) = A241820(n) + A241822(n) for n >= 0.
a(n) + A241818(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 4 partitions: 51, 42, 411, 3111.
MATHEMATICA
z = 30; f[n_] := f[n] = IntegerPartitions[n]; d[p_] := d[p] = Length[DeleteDuplicates[p]]; g[p_] := Max[-Differences[p]];
Table[Count[f[n], p_ /; g[p] < d[p]], {n, 0, z}] (* A241818 *)
Table[Count[f[n], p_ /; g[p] <= d[p]], {n, 0, z}] (* A241819 *)
Table[Count[f[n], p_ /; g[p] == d[p]], {n, 0, z}] (* A241820 *)
Table[Count[f[n], p_ /; g[p] >= d[p]], {n, 0, z}] (* A241821 *)
Table[Count[f[n], p_ /; g[p] > d[p]], {n, 0, z}] (* A241822 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 30 2014
STATUS
approved