26140

Appears in sequences

• a(n) = a(n-1) + a(n-1-(number of odd terms so far)).at n=39A007604
• Same rule as Aitken triangle (A011971) except a(0,0)=0, a(1,0)=1.at n=49A046936
• Number of ways to place n nonattacking composite pieces rook + rider[5,6] on an n X n chessboard.at n=7A189863
• Expansion of Product_{k>=0} ((1+x^(3*k+1))/(1-x^(3*k+1)))^2.at n=27A261649
• Number of maximal primitive subsets of {1..n}.at n=48A326077