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A057981 Number of singular n X n (-1,0,1)-matrices. 3
0, 1, 33, 7875, 15099201, 237634987683 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..5.

Eric Weisstein's World of Mathematics, Singular Matrix.

FORMULA

a(n) = A060722(n) - A056989(n). - Alois P. Heinz, Dec 02 2019

CROSSREFS

Complement of A056989.

Cf. A060722, A330134.

Sequence in context: A330134 A210069 A316777 * A219563 A183237 A099828

Adjacent sequences:  A057978 A057979 A057980 * A057982 A057983 A057984

KEYWORD

nonn,more

AUTHOR

Eric W. Weisstein, Oct 23 2000

EXTENSIONS

a(5) from Giovanni Resta, Feb 20 2009

a(0)=0 prepended by Alois P. Heinz, Dec 02 2019

STATUS

approved

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Last modified September 26 11:01 EDT 2020. Contains 337352 sequences. (Running on oeis4.)