%I #13 Feb 06 2020 16:36:33
%S 1,1,10,280,13960,1023760,99935200,12226859200,1801725932800,
%T 310890328768000,61516405597830400,13735605457885312000,
%U 3416919943285809280000,937247149729410729472000,281051240591439955878400000,91474949907165746668607488000,32117399444469103248129863680000
%N E.g.f.: exp(10*x*G(x)^9) / G(x)^9 where G(x) = 1 + x*G(x)^10 is the g.f. of A059968.
%C In general, Sum_{k=0..n} m^k * n!/k! * binomial(m*n-k-m, n-k) * (k-1)/(n-1) is for m>1 asymptotic to m^(m*(n-1)-1/2) / (m-1)^((m-1)*(n-1)-1/2) * n^(n-2) / exp(n-1). - _Vaclav Kotesovec_, Dec 07 2014
%F Let G(x) = 1 + x*G(x)^10 be the g.f. of A059968, then the e.g.f. A(x) of this sequence satisfies:
%F (1) A'(x)/A(x) = G(x)^9.
%F (2) A'(x) = exp(10*x*G(x)^9).
%F (3) A(x) = exp( Integral G(x)^9 dx ).
%F (4) A(x) = exp( Sum_{n>=1} A234573(n-1)*x^n/n ), where A234573(n-1) = binomial(10*n-2,n)/(9*n-1).
%F (5) A(x) = F(x/A(x)) where F(x) is the e.g.f. of A251590.
%F (6) A(x) = Sum_{n>=0} A251590(n)*(x/A(x))^n/n! and
%F (7) [x^n/n!] A(x)^(n+1) = (n+1)*A251590(n),
%F where A251590(n) = 10^(n-8) * (n+1)^(n-10) * (4782969*n^8 + 50309748*n^7 + 237013938*n^6 + 655232760*n^5 + 1166624361*n^4 + 1374998212*n^3 + 1051760172*n^2 + 479277840*n + 100000000).
%F a(n) = Sum_{k=0..n} 10^k * n!/k! * binomial(10*n-k-10, n-k) * (k-1)/(n-1) for n>1.
%F Recurrence: 81*(3*n-5)*(3*n-4)*(9*n-17)*(9*n-16)*(9*n-14)*(9*n-13)*(9*n-11)*(9*n-10)*(250000*n^8 - 5300000*n^7 + 49332500*n^6 - 263500000*n^5 + 884055975*n^4 - 1909634570*n^3 + 2596659373*n^2 - 2035277286*n + 705468040)*a(n) = 800*(3125000000000*n^17 - 111562500000000*n^16 + 1872125000000000*n^15 - 19618187500000000*n^14 + 143829395937500000*n^13 - 783195370343750000*n^12 + 3281447638218750000*n^11 - 10810863753751875000*n^10 + 28370066880833218750*n^9 - 59681174371832246875*n^8 + 100725400409628775000*n^7 - 135736802338370325750*n^6 + 144424061701272600950*n^5 - 118936947986511839915*n^4 + 73322264536912326596*n^3 - 31942069342168467356*n^2 + 8798129066413437408*n - 1156512281566561920)*a(n-1) + 10000000000*(250000*n^8 - 3300000*n^7 + 19232500*n^6 - 64805000*n^5 + 138543475*n^4 - 193260670*n^3 + 172779013*n^2 - 91243350*n + 22054032)*a(n-2). - _Vaclav Kotesovec_, Dec 07 2014
%F a(n) ~ 10^(10*(n-1)-1/2) / 9^(9*(n-1)-1/2) * n^(n-2) / exp(n-1). - _Vaclav Kotesovec_, Dec 07 2014
%e E.g.f.: A(x) = 1 + x + 10*x^2/2! + 280*x^3/3! + 13960*x^4/4! + 1023760*x^5/5! +...
%e such that A(x) = exp(10*x*G(x)^9) / G(x)^9
%e where G(x) = 1 + x*G(x)^10 is the g.f. of A059968:
%e G(x) = 1 + x + 10*x^2 + 145*x^3 + 2470*x^4 + 46060*x^5 + 910252*x^6 +...
%e Note that
%e A'(x) = exp(10*x*G(x)^9) = 1 + 10*x + 280*x^2/2! + 13960*x^3/3! +...
%e LOGARITHMIC DERIVATIVE.
%e The logarithm of the e.g.f. begins:
%e log(A(x)) = x + 9*x^2/2 + 252*x^3/3 + 12654*x^4/4 + 933984*x^5/5 +...
%e and so A'(x)/A(x) = G(x)^9.
%e TABLE OF POWERS OF E.G.F.
%e Form a table of coefficients of x^k/k! in A(x)^n as follows.
%e n=1: [1, 1, 10, 280, 13960, 1023760, 99935200, 12226859200, ...];
%e n=2: [1, 2, 22, 620, 30760, 2243120, 217911520, 26556406400, ...];
%e n=3: [1, 3, 36, 1026, 50760, 3683880, 356283360, 43256151360, ...];
%e n=4: [1, 4, 52, 1504, 74344, 5374240, 517647520, 62621962240, ...];
%e n=5: [1, 5, 70, 2060, 101920, 7344920, 704861200, 84980501600, ...];
%e n=6: [1, 6, 90, 2700, 133920, 9629280, 921060720, 110691813600, ...];
%e n=7: [1, 7, 112, 3430, 170800, 12263440, 1169680960, 140152067440, ...];
%e n=8: [1, 8, 136, 4256, 213040, 15286400, 1454475520, 173796462080, ...]; ...
%e in which the main diagonal begins (see A251587):
%e [1, 2, 36, 1504, 101920, 9629280, 1169680960, 173796462080, ...]
%e and is given by the formula:
%e [x^n/n!] A(x)^(n+1) = 10^(n-8) * (n+1)^(n-9) * (4782969*n^8 + 50309748*n^7 + 237013938*n^6 + 655232760*n^5 + 1166624361*n^4 + 1374998212*n^3 + 1051760172*n^2 + 479277840*n + 100000000) for n>=0.
%t Flatten[{1,1,Table[Sum[10^k * n!/k! * Binomial[10*n-k-10, n-k] * (k-1)/(n-1),{k,0,n}],{n,2,20}]}] (* _Vaclav Kotesovec_, Dec 07 2014 *)
%o (PARI) {a(n) = local(G=1);for(i=1,n, G = 1 + x*G^10 +x*O(x^n)); n!*polcoeff( exp(10*x*G^9) / G^9, n)}
%o for(n=0, 20, print1(a(n), ", "))
%o (PARI) {a(n) = if(n==0, 1, sum(k=0, n, 10^k * n!/k! * binomial(10*n-k-10,n-k)*if(n==1,1/10,(k-1)/(n-1)) ))}
%o for(n=0, 20, print1(a(n), ", "))
%Y Cf. A251590, A251670, A059968, A234573.
%Y Cf. Variants: A243953, A251573, A251574, A251575, A251576, A251577, A251578, A251579.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Dec 06 2014