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a(n) = n! * n^4.
4

%I #10 Jul 12 2015 19:23:59

%S 0,1,32,486,6144,75000,933120,12101040,165150720,2380855680,

%T 36288000000,584421868800,9932577177600,177849941068800,

%U 3349041234739200,66201014880000000,1371195958099968000,29707369682006016000

%N a(n) = n! * n^4.

%C Denominators in the power series expansion of the higher order exponential integral E(x,4,1) - ((gamma^4/24+Pi^2*gamma^2/24+zeta(3)*gamma/3+Pi^4/160) + (gamma^3/6+ Pi^2*gamma/12+ zeta(3)/3)*log(x) + (gamma^2/4+ Pi^2/24)*log(x)^2 + (gamma/6)*log(x)^3 + log(x)^4/24), n>0. See A163931 for information on the E(x,m,n). - _Johannes W. Meijer_, Oct 16 2009

%F E.g.f.: (x + 11x^2 + 11x^3 + x^4)/(1 - x)^5

%p a:=n->sum(sum(sum((n+1)!-n!, j=1..n),k=1..n),m=1..n): seq(a(n), n=0..17); # _Zerinvary Lajos_, May 16 2007

%t Table[n!n^4, {n, 0, 20}]

%Y Cf. A163931 (E(x,m,n)), A001563 (n*n!), A002775 (n^2*n!), A091363 (n^3*n!). - _Johannes W. Meijer_, Oct 16 2009

%K easy,nonn

%O 0,3

%A Mario Catalani (mario.catalani(AT)unito.it), Jan 07 2004

%E More terms from _Zerinvary Lajos_, May 16 2007