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A182957
G.f.: A(x) = x/Series_Reversion(x*G(x)) where G(x) = Sum_{n>=0} n^n*x^n.
2
1, 1, 3, 17, 151, 1824, 27541, 494997, 10273039, 241217147, 6314907390, 182283959604, 5750796304553, 196865960240416, 7268410972604665, 287920792767378837, 12181570018235995359, 548274960053921957856
OFFSET
0,3
FORMULA
G.f. satisfies: A(x) = G(x/A(x)) where A(x*G(x)) = G(x) = Sum_{n>=0} n^n*x^n.
G.f. satisfies: [x^n] A(x)^(n+1)/(n+1) = n^n.
EXAMPLE
G.f.: A(x) = 1 + x + 3*x^2 + 17*x^3 + 151*x^4 + 1824*x^5 +...
G.f. satisfies A(x) = G(x/A(x)) where A(x*G(x)) = G(x) begins:
G(x) = 1 + x + 2^2*x^2 + 3^3*x^3 + 4^4*x^4 + 5^5*x^5 + 6^6*x^6 +...
so that:
A(x) = 1 + x/A(x) + 2^2*x^2/A(x)^2 + 3^3*x^3/A(x)^3 + 4^4*x^4/A(x)^4 +...
The coefficients in A(x)^n for n=1..8 begin:
A^1: [(1), 1, 3, 17, 151, 1824, 27541, 494997, ...];
A^2: [1,(2), 7, 40, 345, 4052, 59925, 1061154, ...];
A^3: [1, 3,(12), 70, 591, 6762, 97938, 1707987, ...];
A^4: [1, 4, 18,(108), 899, 10044, 142488, 2446336, ...];
A^5: [1, 5, 25, 155,(1280), 14001, 194620, 3288540, ...];
A^6: [1, 6, 33, 212, 1746,(18750), 255532, 4248630, ...];
A^7: [1, 7, 42, 280, 2310, 24423,(326592), 5342541, ...];
A^8: [1, 8, 52, 360, 2986, 31168, 409356, (6588344), ...]; ...
where the coefficient of x^n in A(x)^(n+1)/(n+1) equals n^n.
PROG
(PARI) {a(n)=polcoeff(x/serreverse(sum(m=1, n+1, (m-1)^(m-1)*x^m)+x^2*O(x^n)), n)}
CROSSREFS
Sequence in context: A286345 A303063 A209305 * A307375 A007767 A075820
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Dec 31 2010
STATUS
approved