Column 2 of triangle A121391, where column k of T=A121391 equals column k of T^(k+1) shift down 1 row.
A121393
Column 2 of triangle A121391, where column k of T=A121391 equals column k of T^(k+1) shift down 1 row.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =12a(4) =58a(5) =333a(6) =2268a(7) =18281a(8) =173127a(9) =1905500a(10) =24080964a(11) =345381551a(12) =5563259860a(13) =99716732043
External references
- oeis: A121393