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A243198
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Least number k such that k + DigProd(k) = 10^n.
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1
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5, 91, 919, 7795, 100000, 1000000, 10000000, 100000000, 1000000000, 9968647168, 100000000000, 1000000000000, 9999761914432, 100000000000000, 1000000000000000, 10000000000000000, 100000000000000000, 1000000000000000000, 9999982446427242496
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OFFSET
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1,1
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COMMENTS
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a(n) <= 10^n for all n.
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LINKS
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EXAMPLE
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919 + 9*1*9 = 1000 = 10^3. Since 919 is the smallest number with this property, a(3) = 919.
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PROG
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(PARI) DP(n)={p=1; d=digits(n); return(prod(i=1, #d, d[i]))}
a(n)=for(k=10^n-9^n, 10^n, if((k+DP(k))==10^n, return(k)))
n=1; while(n<100, print1(a(n), ", "); n++)
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CROSSREFS
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KEYWORD
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nonn,base,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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