A048017 Number of nonempty subsets of {1,2,...,n} in which exactly 1/3 of the elements are <= (n-2)/3.

0, 0, 0, 0, 6, 10, 15, 45, 77, 126, 322, 570, 975, 2325, 4213, 7425, 17061, 31421, 56511, 126763, 236203, 431098, 950818, 1787346, 3298527, 7184421, 13598053, 25314061, 54604081, 103918153, 194810143, 416990563, 797154723, 1502994133

Offset

1,5

Links

Table of n, a(n) for n=1..34.

Crossrefs

Sequence in context: A272398 A020159 A357529 * A332392 A048078 A229276

Adjacent sequences: A048014 A048015 A048016 * A048018 A048019 A048020

Keyword

nonn

Author

Clark Kimberling

Status

approved