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A078218
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Smallest multiple of n that begins with the concatenation of the divisors of n (in increasing order).
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1
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1, 12, 132, 124, 15, 1236, 175, 1248, 1395, 12510, 1111, 12346128, 1131, 127148, 13515, 124816, 1173, 12369186, 1197, 12451020, 137214, 12112210, 12305, 1234681224, 1525, 1213264, 1392714, 1247142820, 12905, 12356101530, 13113
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OFFSET
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1,2
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LINKS
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EXAMPLE
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The concatenation of the divisors of 7 is 17; 175 = 25*7 is the smallest multiple of 7 that begins with 17, so a(7) = 175.
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PROG
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(PARI) {for(n=1, 31, k=floor(log(n)/log(10))+1; d=divisors(n); v=Str(); for(i=1, matsize(d)[2], v=concat(v, Str(d[i]))); s=eval(v); t=s+1; m=floor(log(s)/log(10))+1; d=k-m; s=s*10^d; t=t*10^d; b=1; while(b>0, q=floor(s/n); while(b>0&&(p=q*n)<t, if(p>=s, print1(p, ", "); b=0, q++)); s=10*s; t=10*t))}
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CROSSREFS
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KEYWORD
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base,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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