A138315 E.g.f. satisfies: A(x) = exp( Sum_{n>=0} a(n)*x^(2n+1)/(2n+1) ).

1, 1, 1, 3, 9, 45, 225, 3015, 22545, 473625, 4637025, 191508075, 2288273625, 123786785925, 1735168572225, 276775700288175, 4433024011291425, 510439906229029425, 9196849128341801025, 3123191121957643317075

Offset

0,4

Links

Table of n, a(n) for n=0..19.

Example

E.g.f.: A(x) = 1 + x + x^2/2! + 3*x^3/3! + 9*x^4/4! + 45*x^5/5! + 225*x^6/6! +...
Log(A(x)) = x + x^3/3 + x^5/5 + 3*x^7/7 + 9*x^9/9 + 45*x^11/11 + 225*x^13/13 +...

Prog

(PARI) {a(n)=local(A=if(n==0, x, sum(k=0, n\2, a(k)*x^(2*k+1)/(2*k+1)))); n!*polcoeff(exp(A+x*O(x^n)), n)}

Crossrefs

Cf. A138314.

Sequence in context: A000246 A247006 A103620 * A337849 A328267 A038059

Adjacent sequences: A138312 A138313 A138314 * A138316 A138317 A138318

Keyword

nonn

Author

Paul D. Hanna, Mar 13 2008

Status

approved