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A206177 G.f.: exp( Sum_{n>=1} x^n/n * Sum_{k=0..n} binomial(n,k)^3 * 2^k ). 2
1, 3, 15, 93, 657, 5067, 41579, 357297, 3181305, 29133387, 272939679, 2605588317, 25269158105, 248367451299, 2469462766347, 24800305889217, 251258730935697, 2565372042688563, 26373806952805519, 272818956588097341, 2837840577104379201, 29667671262881320347 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Logarithmic derivative yields A206178.

LINKS

Table of n, a(n) for n=0..21.

EXAMPLE

G.f.: A(x) = 1 + 3*x + 15*x^2 + 93*x^3 + 657*x^4 + 5067*x^5 + 41579*x^6 +...

where

log(A(x)) = 3*x + 21*x^2/2 + 171*x^3/3 + 1521*x^4/4 + 14283*x^5/5 + 138909*x^6/6 +...+ A206178(n)*x^n/n +...

PROG

(PARI) {a(n)=polcoeff(exp(sum(m=1, n, x^m/m*sum(k=0, m, binomial(m, k)^3*2^k))+x*O(x^n)), n)}

CROSSREFS

Cf. A206178.

Sequence in context: A103210 A203014 A060066 * A272230 A308457 A241711

Adjacent sequences:  A206174 A206175 A206176 * A206178 A206179 A206180

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Feb 04 2012

STATUS

approved

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Last modified December 5 10:45 EST 2019. Contains 329751 sequences. (Running on oeis4.)