42975796

Appears in sequences

• a(n) = 2*(3*n)! / ((2*n+1)!*(n+1)!).at n=13A000139
• Number of aperiodic necklaces of n beads of 2 colors, 11 of them black.at n=27A032169
• Number of necklaces with 11 black beads and n-11 white beads.at n=28A032196