523250

Appears in sequences

• a(n) = 3^(n-1) - 2^n + 1 (essentially Stirling numbers of second kind).at n=12A028243
• Triangle read by rows: T(n,k) = Sum_{j=0..2k} (-1)^j * binomial(2k,j) * (2+k-j)^(2n).at n=22A390029