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Expansion of (1-25*x)^(3/5).
1

%I #9 Jan 16 2020 08:45:44

%S 1,-15,-75,-875,-13125,-223125,-4090625,-78890625,-1577812500,

%T -32432812500,-681089062500,-14550539062500,-315261679687500,

%U -6911506054687500,-153040491210937500,-3417904303710937500

%N Expansion of (1-25*x)^(3/5).

%F G.f.: (1-25*x)^(3/5).

%F a(n) = (5^n/n!) * Product_{k=0..n-1} (5*k-3).

%F a(n) ~ -3/5*Gamma(2/5)^-1*n^(-8/5)*5^(2*n)*{1 + 12/25*n^-1 + ...}. - Joe Keane (jgk(AT)jgk.org), Nov 24 2001

%e (1-x)^(3/5) = 1 - 3/5*x - 3/25*x^2 - 7/125*x^3 - ...

%t CoefficientList[Series[(1-25*x)^(3/5), {x, 0, 15}], x] (* _Georg Fischer_, Jan 16 2020 *)

%Y Cf. A049380.

%K sign,easy

%O 0,2

%A Joe Keane (jgk(AT)jgk.org)

%E Definition corrected by _Georg Fischer_, Jan 16 2020