A158163 Number of nondecreasing integer sequences of length 29 with sum zero and sum of absolute values 2n.

1, 4, 9, 25, 49, 121, 225, 484, 900, 1764, 3136, 5929, 10201, 18225, 30975, 53353, 88171, 148086, 239666, 391914, 624144, 996519, 1558110, 2444206, 3758817, 5785219, 8774142, 13288255, 19862807, 29658474, 43753984, 64431817, 93942055

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n=1..238

Formula

a(n) = A000041(n)^2 for n <= 14.

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

Crossrefs

Sequence in context: A158160 A158161 A158162 * A158164 A158165 A158166

Adjacent sequences: A158160 A158161 A158162 * A158164 A158165 A158166

Keyword

nonn

Author

R. H. Hardin, Mar 13 2009

Status

approved