A277055
Irregular array by rows: A(n,m) is the least number which gives a pandigital product when multiplied by the m-th repunit in base n; each row is truncated when it reaches its stationary point.
Original entry on oeis.org
2, 11, 8, 5, 75, 15, 7, 694, 119, 34, 8345, 1505, 195, 123717, 105803, 2217, 2134, 727, 2177399, 241934, 37303, 3724, 44317196, 4431858, 487068, 54771, 9124, 1023456789, 93125079, 9222117, 1110789, 92115, 26432593615
Offset: 2
The first rows of the array are:
2, (2, 2...)
11, 8, 5, (5, 5...)
75, 15, 7, (7, 7...)
694, 119, 34,
8345, 1505, 195,
123717, 105803, 2217, 2134, 727,
2177399, 241934, 37303, 3724,
44317196, 4431858, 487068, 54771, 9124,
1023456789, 93125079, 9222117, 1110789, 92115
A277056
Least k such that any sufficiently long repunit multiplied by k is a pandigital number in numerical base n.
Original entry on oeis.org
2, 5, 7, 34, 195, 727, 3724, 9124, 92115, 338161, 2780514, 6871290, 99000993
Offset: 2
Any binary repunit multiplied by 2 is a binary pandigital, so a(2)=2 (10 in binary).
k-th decimal repunit for k>4 multiplied by 92115 gives a decimal pandigital number (see A277054) with no number less than 92115 having the same property, so a(10)=92115.
A277057
Least k such that n-th repunit times k contains all digits from 1 to 9.
Original entry on oeis.org
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
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.
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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
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