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A241760
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 a part of p.
4
0, 0, 0, 1, 0, 0, 2, 1, 2, 2, 3, 2, 6, 5, 8, 9, 11, 11, 17, 17, 23, 26, 32, 36, 47, 51, 63, 71, 84, 93, 115, 127, 151, 171, 201, 225, 266, 297, 346, 389, 448, 501, 580, 648, 740, 831, 945, 1056, 1201, 1340, 1517, 1695, 1910, 2130, 2399, 2670
OFFSET
0,7
FORMULA
a(n) + A241761(n) = A000041(n) for n >= 0.
EXAMPLE
a(6) counts these 2 partitions: 42, 321.
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