Numbers k such that Sum_{j=1..k-1} (2*j)!/4^j is an integer.
A216042
Numbers k such that Sum_{j=1..k-1} (2*j)!/4^j is an integer.
Terms
- a(0) =1a(1) =3a(2) =53a(3) =106a(4) =427a(5) =3416a(6) =6806a(7) =13665a(8) =27330a(9) =130030a(10) =220227a(11) =437666
External references
- oeis: A216042