A158142 Number of nondecreasing integer sequences of length 8 with sum zero and sum of absolute values 2n.

1, 4, 9, 25, 46, 103, 163, 307, 478, 791, 1143, 1818, 2495, 3663, 4994, 7002, 9154, 12532, 15986, 21200, 26726, 34398, 42532, 54145, 65791, 81872, 98871, 121163, 144174, 175083, 206075, 246947, 289116, 342271, 397027, 467462, 537495, 626427

Offset

1,2

Comments

a(n) = A000041(n)^2 for n<=4

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..689

Crossrefs

Sequence in context: A341790 A350152 A350322 * A158143 A082200 A244557

Adjacent sequences: A158139 A158140 A158141 * A158143 A158144 A158145

Keyword

nonn

Author

R. H. Hardin Mar 13 2009

Status

approved