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A255357
Natural numbers n, other than multiples of 10, such that n, n^2 and n^3 lack the digit 1 in their decimal expansion.
2
2, 3, 7, 62, 63, 65, 66, 67, 74, 76, 77, 78, 84, 86, 87, 92, 93, 94, 95, 202, 207, 274, 275, 282, 284, 287, 288, 292, 295, 298, 305, 307, 452, 453, 457, 587, 588, 592, 594, 607, 624, 632, 635, 636, 637, 638, 653, 664, 665, 666, 667, 668, 675, 686, 688, 695, 697, 698, 702, 703, 705, 707
OFFSET
1,1
LINKS
EXAMPLE
Numbers {2, 3, 7, 62, 63}, their squares {4, 9, 49, 3844, 3969} and cubes {8, 27, 343, 238328, 250047} all are "one-less".
MAPLE
filter:= proc(n) local L, i;
for i from 1 to 3 do
L:= convert(n^i, base, 10);
if member(1, L) then return false fi;
od;
true
end proc:
select(filter, [seq(seq(10*i+j, j=2..8), i=0..100)]); # Robert Israel, Apr 03 2024
MATHEMATICA
Select[Range[800], NumberDigit[#, 0]!=0&&FreeQ[Flatten[ IntegerDigits/@ {#, #^2, #^3}], 1]&] (* Harvey P. Dale, Sep 24 2021 *)
CROSSREFS
KEYWORD
nonn,base,look
AUTHOR
Zak Seidov, Feb 23 2015
EXTENSIONS
Definition modified by Harvey P. Dale, Sep 24 2021
STATUS
approved