a(0)=a(1)=1; thereafter a(n) = (4*n-3)*a(n-1) + 2*a(n-2).
A272646
a(0)=a(1)=1; thereafter a(n) = (4*n-3)*a(n-1) + 2*a(n-2).
Terms
- a(0) =1a(1) =1a(2) =7a(3) =65a(4) =859a(5) =14733a(6) =311111a(7) =7807241a(8) =227032211a(9) =7507677445a(10) =278238129887
External references
- oeis: A272646