147090

Appears in sequences

• a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers).at n=18A024469
• a(n) = Sum_{k=0..n-1} T(n,k)*T(n,2n-k), T given by A027960.at n=9A027980
• Number of homogeneous generators of degree n for graded algebra associated with meanders.at n=11A060149
• The number of random walks on the simple square lattice that return to the origin (0,0) after 2n steps and do not pass through (0,0) or (1,0) at intermediate steps.at n=5A337869