A158168 Number of nondecreasing integer sequences of length 34 with sum zero and sum of absolute values 2n.

1, 4, 9, 25, 49, 121, 225, 484, 900, 1764, 3136, 5929, 10201, 18225, 30976, 53361, 88209, 148222, 240082, 393055, 627015, 1003270, 1573058, 2475727, 3822289, 5908531, 9005651, 13711877, 20618252, 30980134, 46019177, 68255375, 100287771

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n=1..222

Formula

a(n) = A000041(n)^2 for n <= 17.

a(n) = A000041(n)^2 - cumulative A000712(2*n-1-length), 0 <= 2*n-1-length <= floor(n/2) [empirical].

Crossrefs

Sequence in context: A158165 A158166 A158167 * A158169 A158170 A158171

Adjacent sequences: A158165 A158166 A158167 * A158169 A158170 A158171

Keyword

nonn

Author

R. H. Hardin, Mar 13 2009

Status

approved