a(n) = P_n(7), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 7*x + 12*x^2)^n.
A084768
a(n) = P_n(7), where P_n is n-th Legendre polynomial; also, a(n) = central coefficient of (1 + 7*x + 12*x^2)^n.
Terms
- a(0) =1a(1) =7a(2) =73a(3) =847a(4) =10321a(5) =129367a(6) =1651609a(7) =21360031a(8) =278905249a(9) =3668760487a(10) =48543499753a(11) =645382441711
External references
- oeis: A084768