142592

Appears in sequences

• Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1),U=(1,2), or d=(1,-1) and have k pyramids of the first kind (a pyramid of the first kind is a sequence u^pd^p for some positive integer p, starting at the x-axis).at n=38A108451
• Number of (n+7)X(n+7) 0..1 matrices with each 8X8 subblock idempotent.at n=7A224589
• Expansion of Product_{k>=0} ((1+x^(3*k+1))/(1-x^(3*k+1)))^2.at n=35A261649
• G.f.: Sum_{k>=1} x^(2*k-1)/(1+x^(2*k-1)) * Product_{k>=1} 1/(1-x^k).at n=44A305123