0,2

G.f.: (1-25*x)^(-4/5).

a(n) = (5^n/n!) * product[ k=0..n-1 ] (5*k+4).

a(n) ~ Gamma(4/5)^-1*n^(-1/5)*5^(2*n)*{1 - 2/25*n^-1 + ...}. - Joe Keane (jgk(AT)jgk.org), Nov 24 2001

(1-x)^(-4/5) = 1 + 4/5*x + 18/25*x^2 + 84/125*x^3 + ...

Cf. A008546, A049393, A049397, A049381.

Sequence in context: A136257 A099278 A111158 this_sequence A065412 A159753 A000827

Adjacent sequences: A049379 A049380 A049381 this_sequence A049383 A049384 A049385

nonn,easy

Joe Keane (jgk(AT)jgk.org)