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 A306838 Number of different values taken by the determinant of a real (-1,0,1) matrix of order n. 0
 1, 3, 5, 9, 25, 67 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Every term in this sequence is odd, since 0 is a possible determinant, and if d is a possible determinant then so is -d. a(n) >= 1 + 2^n, since every integer determinant between -2^(n-1) and 2^(n-1) is possible (see MathOverflow link). LINKS Steven E. Thornton, Properties of the Bohemian family of n x n matrices with population {-1, 0, 1}, Characteristic Polynomial Database. EXAMPLE For n = 2, the possible determinants of a 2x2 matrix with entries from {-1,0,1} are -2, -1, 0, 1, and 2. Since there are 5 numbers in this list, a(2) = 5. The possible nonnegative determinants for small values of n are as follows (all the negatives of these numbers are also possible determinants): n = 1: 0, 1 n = 2: 0, 1, 2 n = 3: 0, 1, 2, 3, 4 n = 4: 0 through 10, 12, 16 n = 5: 0 through 28, 30, 32, 36, 40, 48 CROSSREFS Number of matrices having maximum determinant is in A051753. Sequence in context: A251413 A039774 A114001 * A171879 A171877 A339068 Adjacent sequences: A306835 A306836 A306837 * A306839 A306840 A306841 KEYWORD nonn,more,hard AUTHOR Steven E. Thornton, Mar 12 2019 EXTENSIONS Edited and expanded by Nathaniel Johnston, Apr 19 2022 STATUS approved

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Last modified November 28 17:22 EST 2022. Contains 358421 sequences. (Running on oeis4.)