A277057 Least k such that n-th repunit times k contains all digits from 1 to 9.

123456789, 11225079, 1113198, 210789, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115, 11115

Offset: 1

Author

Andrey Zabolotskiy and Altug Alkan, Sep 26 2016

Keywords

• nonn
• base
• easy

Comments

Starting from n=5, a(n)=A277059(10)=11115, and the corresponding pandigital numbers are 123499...98765 (n-4 nines). Actually, for all n, the resulting numbers are zeroless pandigitals.

a(1)-a(5) constitute row 10 of A277058.

a(n)*A002275(n) is 123456789, 123475869, 123564978, 234186579, 123498765, ...

Examples

			a(2) = 11225079 because A002275(2)*11225079 = 11*11225079 = 123475869 that contains all digits from 1 to 9 and 11225079 is the least number with this property.
		

Crossrefs

Cf. A002275, A050289, A277054, A277058, A277059.

Programs

PARI

isok(n) = my(d=digits(n)); vecmin(d) && (#Set(digits(n)) == 9);
a(n) = {if (n==1, return(123456789)); my(k=1); while(! isok(k*(10^n - 1)/9), k++); k;} \\ Michel Marcus, Sep 26 2019