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A241761
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)) is not a part of p.
4
1, 1, 2, 2, 5, 7, 9, 14, 20, 28, 39, 54, 71, 96, 127, 167, 220, 286, 368, 473, 604, 766, 970, 1219, 1528, 1907, 2373, 2939, 3634, 4472, 5489, 6715, 8198, 9972, 12109, 14658, 17711, 21340, 25669, 30796, 36890, 44082, 52594, 62613, 74435, 88303, 104613, 123698
OFFSET
0,3
COMMENTS
The partition {n} is included in the count.
FORMULA
a(n) + A241760(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 6 partitions: 6, 51, 411, 33, 3111, 222, 2211, 21111, 111111.
MATHEMATICA
z = 55; f[n_] := f[n] = IntegerPartitions[n]; g[p_] := Max[-Differences[p]]; g1[p_] := Min[-Differences[p]];
Table[Count[f[n], p_ /; MemberQ[p, g[p]]], {n, 0, z}] (* A241735 *)
Table[Count[f[n], p_ /; ! MemberQ[p, g[p]]], {n, 0, z}] (* A241736 *)
Table[Count[f[n], p_ /; MemberQ[p, g1[p]]], {n, 0, z}] (* A241760 *)
Table[Count[f[n], p_ /; ! MemberQ[p, g1[p]]], {n, 0, z}](* A241761 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Apr 28 2014
STATUS
approved