A047178 Number of nonempty subsets of {1,2,...,n} in which exactly 3/5 of the elements are <= (n-1)/2.

0, 0, 0, 0, 0, 0, 6, 10, 40, 60, 150, 210, 455, 630, 1470, 2142, 5544, 8400, 21630, 32802, 80520, 121110, 290400, 437580, 1056627, 1608607, 3929926, 6034600, 14742910, 22712326, 55107598, 84996158, 205272008, 317302008

Offset

1,7

Links

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

Crossrefs

Sequence in context: A038264 A094890 A213477 * A132095 A332441 A153328

Adjacent sequences: A047175 A047176 A047177 * A047179 A047180 A047181

Keyword

nonn

Author

Clark Kimberling

Status

approved