123790

Appears in sequences

• a(n) = floor(n*2^n/(n + 1)).at n=17A350294
• a(n) is the number of tetrapods standing on the four edges of an n X n grid, so that no two feet are the same distance apart and no foot is on a corner. Tetrapods with congruent footprints are counted only once.at n=31A353447
• a(n) is the number whose base-4 digits are 1 followed by the first n-1 terms of the periodic sequence with initial period 3,2,0.at n=8A378502