O.g.f.: A(x) = Sum_{n>=0} x^n*Product_{k=0..n} (1 + k*(k+1)/2*x).
A124381
O.g.f.: A(x) = Sum_{n>=0} x^n*Product_{k=0..n} (1 + k*(k+1)/2*x).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =14a(5) =48a(6) =181a(7) =772a(8) =3620a(9) =18511a(10) =102869a(11) =613584a(12) =3926895a(13) =26734671a(14) =193310243a(15) =1477081245a(16) =11896869336a(17) =100700815331a(18) =893438783126
External references
- oeis: A124381