197574

Appears in sequences

• Whitney number of level n of the lattice of the ideals of the crown of size 2 n.at n=15A051292
• a(n) gives the A-sequence for the Riordan matrix (1/(1 + x^2 - x^3), x/(1 + x^2 - x^3)) from A321196.at n=19A321197
• Number of 4-cycles in the n-cycle complement and (n+1)-wheel complement graph.at n=36A367985