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A167668
Nonnegative integers n such that n^j doesn't contain the digit j (1<=j<=7) and n is not a multiple of a smaller member of the sequence.
0
0, 42, 6008, 22738
OFFSET
1,2
COMMENTS
If multiples could appear in the sequence, then 10^x * 22738 would also be in the sequence.
I've tested the integers up to 100000000. I believe 22738 is the greatest integer with this property, but I don't have a proof.
Similarly, I think there's no integer with the same property up to 8, but again, I have no proof of this.
EXAMPLE
Example : 22738 is in the sequence, because
The digit 1 doesn't appear in 22738^1
The digit 2 doesn't appear in 22738^2 = 517016644
The digit 3 doesn't appear in 22738^3 = 11755924451272
The digit 4 doesn't appear in 22738^4 = 267306210173022736
The digit 5 doesn't appear in 22738^5 = 6078008606914190971168
The digit 6 doesn't appear in 22738^6 = 138201759704014874302417984
The digit 7 doesn't appear in 22738^7 = 3142431612149890211888380120192
CROSSREFS
Sequence in context: A101630 A273628 A005791 * A277665 A215837 A211908
KEYWORD
fini,nonn,base
AUTHOR
Jean-Marc Falcoz, Nov 08 2009
STATUS
approved