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A118713 a(n) = determinant of n X n circulant matrix whose first row is A001358(1), A001358(2), ..., A001358(n) where A001358(n) = n-th semiprime. +0
8
4, -20, 361, -3567, 218053, -3455872, 736439027, -16245418225, 1519211613654 (list; graph; listen)
OFFSET

1,1

COMMENT

Semiprime analogue of A066933 Circulant of prime numbers. a(n) alternates in sign. A048954 Wendt determinant of n-th circulant matrix C(n). A052182 Circulant of natural numbers. A086459 Circulant of powers of 2.

LINKS

Eric Weisstein's World of Mathematics, Circulant Matrix.

EXAMPLE

a(2) = -20 = determinant

|4,6|

|6,4|.

a(3) = 361 = 19^2 = determinant

|4,6,9|

|9,4,6|

|6,9,4|.

CROSSREFS

Cf. A001358, A048954, A052182, A066933, A086459, A086569.

Sequence in context: A120599 A012797 A054465 this_sequence A160703 A132511 A144989

Adjacent sequences: A118710 A118711 A118712 this_sequence A118714 A118715 A118716

KEYWORD

easy,sign

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), May 20 2006

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion of Andrew Plewe, Aug 23 2007

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


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