a(n) = Sum_{k=0..floor((n-1)/3)} 2^k * Stirling2(n,3*k+1).
A357783
a(n) = Sum_{k=0..floor((n-1)/3)} 2^k * Stirling2(n,3*k+1).
Terms
- a(0) =0a(1) =1a(2) =1a(3) =1a(4) =3a(5) =21a(6) =131a(7) =705a(8) =3515a(9) =17389a(10) =91739a(11) =547889a(12) =3746227a(13) =28241373a(14) =224124083a(15) =1821051233a(16) =15023818091a(17) =126366334125
External references
- oeis: A357783