A158145 Number of nondecreasing integer sequences of length 11 with sum zero and sum of absolute values 2n.

1, 4, 9, 25, 49, 120, 217, 446, 773, 1408, 2279, 3955, 6073, 9760, 14692, 22467, 32445, 48073, 67444, 96568, 132921, 184487, 248245, 338391, 446533, 594557, 774198, 1012918, 1297749, 1674816, 2117060, 2691887, 3368516, 4226714, 5231183, 6500798

Offset

1,2

Comments

a(n) = A000041(n)^2 for n<=5

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

Links

R. H. Hardin, Table of n, a(n) for n=1..495

Crossrefs

Sequence in context: A182988 A158144 A247136 * A372743 A082180 A246131

Adjacent sequences: A158142 A158143 A158144 * A158146 A158147 A158148

Keyword

nonn

Author

R. H. Hardin Mar 13 2009

Status

approved