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A138293 E.g.f. satisfies: A(x) = x + exp(x*A(x)). 0
1, 2, 5, 28, 245, 2816, 40537, 702976, 14270153, 332102656, 8719631981, 255020847104, 8222803663549, 289815184113664, 11085650268060929, 457386463819595776, 20248713707077863953, 957435459515190345728 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n) = n!*Sum_{k=0..floor((n+1)/2)} (n-2*k+1)^(n-k)/(k!*(n-2*k+1)!). - Vladeta Jovovic (vladeta(AT)eunet.rs), Mar 15 2008

EXAMPLE

E.g.f: A(x) = 1 + 2*x + 5/2*x^2 + 14/3*x^3 + 245/24*x^4 + 352/15*x^5 +...

Log(A(x)-x) = x + 2*x^2 + 5/2*x^3 + 14/3*x^4 + 245/24*x^5 + 352/15*x^6 +...

PROG

(PARI) {a(n)=local(A=1); for(i=0, n, A=x+exp(x*A+x*O(x^n))); n!*polcoeff(A, n)}

CROSSREFS

Sequence in context: A072371 A019043 A009635 * A068069 A105787 A110497

Adjacent sequences:  A138290 A138291 A138292 * A138294 A138295 A138296

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Mar 13 2008

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Last modified February 16 21:14 EST 2012. Contains 205971 sequences.