79647

Appears in sequences

• Number of subsequences of [ 1,...,n ] in which each odd number has an even neighbor.at n=18A007455
• Number of subsequences of [ 1,...,n ] in which each even number has an odd neighbor.at n=18A007481
• a(n) is the number of subsequences of [ 1, ..., 2n ] in which each odd number has an even neighbor.at n=9A007482
• Number of stacks of n triangles, pointing upwards or downwards depending on row parity.at n=20A224704