33011550

Appears in sequences

• a(n) = (3^n/n!)*Product_{k=0..n-1} (3*k + 1). 3-central binomial coefficients.at n=9A004987
• Square array read by antidiagonals downwards: super Patalan numbers of order 3.at n=45A248324
• Riordan array (1/(1-9x)^(1/3), x/(9x-1)).at n=45A283150
• Square array T(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of 1/(1 - 9*x*(1 + x)^k)^(1/3).at n=54A361839
• Square array T(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of 1/(1 - 9*x*(1 - x)^k)^(1/3).at n=54A361840