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A086875
Sum of rank(M) over all n X n matrices over Z with all entries zero or one.
2
1, 21, 1147, 211965, 143331811, 366753209781
OFFSET
1,2
COMMENTS
The unlikely-looking symbol "+:=" in the MAGMA code is in fact correct. - N. J. A. Sloane, Feb 02 2009
FORMULA
a(n) = Sum_{k=1..n} k * A064230(n,k). - Alois P. Heinz, Jun 18 2022
PROG
(Magma) for a in [1..5] do b := 0; for c in CartesianPower([0, 1], a^2) do b +:= Rank(Matrix(a, a, [aa : aa in c])); end for; print b; end for;
CROSSREFS
Cf. A064230.
Sequence in context: A357314 A270505 A086098 * A012211 A297071 A036059
KEYWORD
hard,more,nonn
AUTHOR
Tom Womack (tom(AT)womack.net), Aug 21 2003
EXTENSIONS
a(6) from Alois P. Heinz, Jun 18 2022
STATUS
approved