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A373102
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Determinants of Hankel matrices corresponding to digits of numbers with an odd number of digits.
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1
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0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, -16, -15, -14, -13, -12, -11, -10, -9, -8, -7, -25, -24, -23, -22, -21, -20, -19, -18, -17, -16, -36, -35, -34, -33, -32, -31, -30
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OFFSET
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1,3
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LINKS
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FORMULA
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a((21 + 100^(i + 1))/11 + 100*x + z + 1) = a((21 + 100^(i + 1))/11 + 100*x + z) + a((21 + 100^i)/11 + x) for 0 <= x < 9 * 10^i, 0 <= z <= 98 with z !== 9 (mod 10).
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EXAMPLE
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a(13) = 2 because the 13th number with an odd number of digits is 102 and the Hankel matrix
[ 1 0 ]
[ 0 2 ]
formed from the digits 1,0,2 has determinant 2.
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MAPLE
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f:= proc(n)
Determinant(HankelMatrix(convert(n, base, 10)))
end proc;
map(f, [$0..9, $100..999]);
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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