%I #8 Dec 27 2017 01:34:23
%S 1,70,3185,120050,4084101,130590390,4012419145,120031392250,
%T 3525181576301,102196720335710,2935410756419505,83751552660170850,
%U 2377917929557166101,67273652916778177030,1898215473677945050265
%N Fourth column of triangle A075502.
%C The e.g.f. given below is Sum_{m=0..3} A075513(4,m)*exp(7*(m+1)*x)/3!.
%F a(n) = A075502(n+4, 4) = (7^n)*S2(n+4, 4) with S2(n, m) := A008277(n, m) (Stirling2).
%F a(n) = (-7^n + 24*14^n - 81*21^n + 64*28^n)/3!.
%F G.f.: 1/Product_{k=1..4} (1 - 7*k*x).
%F E.g.f.: (d^4/dx^4)(((exp(7*x)-1)/7)^4)/4! = (-exp(7*x) + 24*exp(14*x) - 81*exp(21*x) + 64*exp(28*x))/3!.
%Y Cf. A075922, A075924.
%K nonn,easy
%O 0,2
%A _Wolfdieter Lang_, Oct 02 2002
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