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A053765
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a(n) = 4^(n^2 - n).
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8
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1, 1, 16, 4096, 16777216, 1099511627776, 1152921504606846976, 19342813113834066795298816, 5192296858534827628530496329220096, 22300745198530623141535718272648361505980416
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OFFSET
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0,3
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COMMENTS
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Number of nilpotent n X n matrices over GF(4).
(-1)^n * resultant of the Chebyshev polynomial of first kind of degree n and Chebyshev polynomial of first kind of degree 2n (cf. A039991). - Benoit Cloitre, Jan 26 2003
a(n) is the number of spanning subgraphs (or equivalently sets of edges) in the n X n grid graph. - Andrew Howroyd, Jan 29 2023
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REFERENCES
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N. J. Fine and I. N. Herstein, The probability that a matrix be nilpotent, Illinois J. Math., 2 (1958), 499-504.
M. Gerstenhaber, On the number of nilpotent matrices with coefficients in a finite field. Illinois J. Math., Vol. 5 (1961), 330-333.
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LINKS
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PROG
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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