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A050744
Numbers k such that the decimal expansion of k^5 contains no pair of consecutive equal digits.
2
0, 1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 14, 15, 16, 17, 21, 22, 23, 24, 25, 27, 28, 31, 33, 34, 35, 37, 38, 42, 45, 46, 48, 49, 51, 52, 53, 54, 55, 57, 58, 62, 64, 67, 69, 72, 73, 75, 77, 82, 83, 86, 87, 91, 92, 96, 97, 98, 105, 108, 109, 112, 113, 114, 121, 122, 123, 124, 125
OFFSET
1,3
LINKS
MAPLE
filter:= proc(n) local L;
L:= convert(n^5, base, 10);
not member(0, L[2..-1]-L[1..-2])
end proc:
select(filter, [$0..1000]); # Robert Israel, Aug 27 2018
MATHEMATICA
Select[Range[0, 200], SequenceCount[IntegerDigits[#^5], {x_, x_}]==0&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Sep 01 2017 *)
CROSSREFS
Cf. A050752.
Sequence in context: A141819 A097904 A094387 * A078448 A212289 A191840
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Sep 15 1999
EXTENSIONS
Offset changed to 1 by Robert Israel, Aug 27 2018
STATUS
approved