A281678
Numbers k that have no digits in common with k^7.
Original entry on oeis.org
3, 7, 8, 33, 43, 77, 93, 272, 332, 662, 7757, 31333
Offset: 1
43 is a term because 43^7 = 271818611107 has no digit 4 or 3.
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select(t -> convert(convert(t,base,10),set) intersect convert(convert(t^7,base,10),set) = {},
{seq(seq(10*i+j,j=[2,3,7,8]),i=0..10^4});
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Select[Range[40000], Intersection[IntegerDigits[#], IntegerDigits[ #^7]] == {}&] (* Vincenzo Librandi, Jan 27 2017 *)
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isok(n) = #setintersect(Set(digits(n)), Set(digits(n^7))) == 0; \\ Michel Marcus, Jan 26 2017
A253575
Primes p such that digits of p do not appear in p^6.
Original entry on oeis.org
2, 3, 13, 44449
Offset: 1
2 and 2^6 = 64 have no digits in common, hence 2 is in the sequence.
Cf. similar sequences listed in
A253574.
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select(t -> isprime(t) and convert(convert(t,base,10),set) intersect convert(convert(t^6,base,10),set) = {},
{2, seq(i,i=3..10^5,2)}); # Robert Israel, May 25 2025
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Select[Prime[Range[1000000]], Intersection[IntegerDigits[#], IntegerDigits[#^6]]=={} &]
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from sympy import isprime
A253575_list = [n for n in range(1,10**6) if set(str(n)) & set(str(n**6)) == set() and isprime(n)]
# Chai Wah Wu, Jan 05 2015
Showing 1-2 of 2 results.
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