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A014070 C(2^n,n). 36
1, 2, 6, 56, 1820, 201376, 74974368, 94525795200, 409663695276000, 6208116950265950720, 334265867498622145619456, 64832175068736596027448301568, 45811862025512780638750907861652480 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

a(n) is the number of n X n (0,1) matrices with distinct rows modulo rows permutations . - Yuval Dekel (dekelyuval(AT)hotmail.com), Nov 13 2003

FORMULA

G.f.: A(x) = Sum_{n>=0} log(1 + 2^n*x)^n / n!. - Paul D. Hanna (pauldhanna(AT)juno.com), Dec 28 2007

MATHEMATICA

Table[Binomial[2^n, n], {n, 0, 20}] (*From Vladimir Joseph Stephan Orlovsky, Mar 03 2011*)

PROG

(PARI) a(n)=binomial(2^n, n) (PARI) /* G.f. A(x) as Sum of Series: */ {a(n)=polcoeff(sum(k=0, n, log(1+2^k*x +x*O(x^n))^k/k!), n)} - Paul D. Hanna (pauldhanna(AT)juno.com), Dec 28 2007

CROSSREFS

Cf. A088229.

Sequence in context: A074023 A000146 A167010 * A198445 A132525 A074167

Adjacent sequences:  A014067 A014068 A014069 * A014071 A014072 A014073

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 15 10:28 EST 2012. Contains 205763 sequences.