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Search: id:A132683
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A132683 a(n) = C(2^n + n, n). +0
4
1, 3, 15, 165, 4845, 435897, 131115985, 138432467745, 525783425977953, 7271150092378906305, 368539102493388126164865, 68777035446753808820521420545, 47450879627176629761462147774626305 (list; graph; listen)
OFFSET

0,2

FORMULA

a(n) = [x^n] 1/(1-x)^(2^n + 1).

G.f.: Sum_{n>=0} (-log(1 - 2^n*x))^n / ((1 - 2^n*x)*n!). [From Paul D. Hanna (pauldhanna(AT)juno.com), Feb 25 2009]

EXAMPLE

Contribution from Paul D. Hanna (pauldhanna(AT)juno.com), Feb 25 2009: (Start)

G.f.: A(x) = 1 + 3*x + 15*x^2 + 165*x^3 + 4845*x^4 + 435897*x^5 +...

A(x) = 1/(1-x) - log(1-2x)/(1-2x) + log(1-4x)^2/((1-4x)*2!) - log(1-8x)^3/((1-8x)*3!) +-... (End)

PROGRAM

(PARI) a(n)=binomial(2^n+n, n)

(PARI) {a(n)=polcoeff(sum(m=0, n, (-log(1-2^m*x))^m/((1-2^m*x +x*O(x^n))*m!)), n)} [From Paul D. Hanna (pauldhanna(AT)juno.com), Feb 25 2009]

CROSSREFS

Cf. A060690, A132684.

Cf. A066384. [From Paul D. Hanna (pauldhanna(AT)juno.com), Feb 25 2009]

Sequence in context: A080696 A015013 A153280 this_sequence A059386 A077792 A153079

Adjacent sequences: A132680 A132681 A132682 this_sequence A132684 A132685 A132686

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Aug 26 2007

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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