A048008 Number of nonempty subsets of {1,2,...,n} in which exactly 1/4 of the elements are <= (n-1)/3.

0, 0, 0, 1, 4, 10, 20, 41, 77, 126, 252, 505, 844, 1780, 3652, 5995, 12545, 25805, 41951, 88634, 184736, 299411, 636524, 1334942, 2154104, 4594244, 9685364, 15584085, 33355944, 70639794, 113406028, 243374923, 517215283, 828748052

Offset

1,5

Links

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

Crossrefs

Sequence in context: A100354 A352666 A275358 * A048019 A189586 A019498

Adjacent sequences: A048005 A048006 A048007 * A048009 A048010 A048011

Keyword

nonn

Author

Clark Kimberling

Status

approved