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A213880
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a(n) = sum of n-digit numbers with distinct nonzero digits.
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0
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OFFSET
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1,1
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REFERENCES
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H. E. Dudeney, Amusements in Mathematics, Dover, NY, 1917, pp. 17, 160.
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LINKS
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FORMULA
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a(n) = 5*(10^n - 1)*8!/(9 - n)!.
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MATHEMATICA
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Table[5*(10^n - 1)*8!/(9 - n)!, {n, 9}]
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PROG
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(Magma) [ 5*(10^n-1)*Factorial(8)/Factorial(9-n) : n in [1..9]]
(PARI) vector(9, n, 5*(10^n-1)*8!/(9-n)!)
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CROSSREFS
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KEYWORD
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base,easy,fini,full,nonn
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AUTHOR
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STATUS
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approved
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