A158139 Number of nondecreasing integer sequences of length 5 with sum zero and sum of absolute values 2n.

1, 4, 8, 17, 23, 44, 54, 85, 107, 150, 178, 247, 281, 366, 422, 527, 591, 734, 808, 975, 1079, 1272, 1388, 1633, 1761, 2036, 2204, 2513, 2695, 3068, 3266, 3677, 3923, 4374, 4638, 5167, 5449, 6022, 6362, 6983, 7343, 8054, 8436, 9199, 9647, 10464, 10936

Offset: 1

Author

R. H. Hardin Mar 13 2009

Keywords

• nonn

Comments

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

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..999