433026
domain: N
Appears in sequences
- a(n) = Sum_{k=0..2n} (k+1) * A025177(n, k).at n=10A027261
- A convolution triangle of numbers obtained from A036068.at n=45A030524
- Expansion of (-1+1/(1-3*x)^3)/(9*x).at n=9A036068
- Triangle T, read by rows, where matrix power T^3 has powers of 3 in the secondary diagonal: [T^3](n+1,n) = 3^(n+1), with all 1's in the main diagonal and zeros elsewhere.at n=15A117252
- Column 0 of triangle A117252.at n=5A117253
- Number of permutations of 2 indistinguishable copies of 1..n arranged in a circle with exactly 1 local maximum.at n=9A159715
- Numbers k such that rad(k)^2 divides sigma(k).at n=21A173615