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A023813 n^(n*(n+1)/2). 7
1, 8, 729, 1048576, 30517578125, 21936950640377856, 459986536544739960976801, 324518553658426726783156020576256, 8727963568087712425891397479476727340041449, 10000000000000000000000000000000000000000000000000000000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Determinant of n X n matrix M_(i,j)=binomial(n*i,j) - Benoit Cloitre (benoit7848c(AT)orange.fr), Sep 13 2003

Number of commutative binary operations on an n-set. Labeled commutative groupoids.

LINKS

Eric Postpischil Posting to sci.math newsgroup, May 21 1990

Index entries for sequences related to groupoids

MAPLE

seq(mul(n^k, k=1..n), n=0..10); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 03 2007

with(combinat):a:=n->mul(mul(n, i=1..k), k=0..n): seq(a(n), n=0..10); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 03 2007

CROSSREFS

a(n)+A079182(n)=A002489(n)

Cf. A001425, A002489, A023814, A023815.

Sequence in context: A046188 A014387 A017007 * A068895 A115590 A134923

Adjacent sequences:  A023810 A023811 A023812 * A023814 A023815 A023816

KEYWORD

easy,nonn

AUTHOR

Lyle Ramshaw (ramshaw(AT)pa.dec.com)

EXTENSIONS

Better description from Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Dec 29 2001

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Last modified February 16 10:53 EST 2012. Contains 205904 sequences.