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A257197 Numbers k such that the decimal expansions of both k and k^2 have 1 as smallest digit and 6 as largest digit. 16
116, 146, 1116, 1146, 1156, 1246, 1465, 1556, 1616, 3516, 3621, 4611, 4621, 4631, 11116, 11146, 11156, 11465, 11556, 11642, 15216, 16231, 21556, 22631, 25146, 25162, 25621, 33516, 34156, 35116, 35146, 35162, 36211, 36215, 36512, 46111, 46112, 46211, 46331 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
MATHEMATICA
sd1Q[n_]:=Module[{idn=IntegerDigits[n]}, Min[idn]==1&&Max[idn]==6]; Select[ Range[50000], AllTrue[{#, #^2}, sd1Q]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Nov 22 2020 *)
PROG
(PARI) is(n) = vecmin(digits(n))==1 && vecmin(digits(n^2))==1 && vecmax(digits(n))==6 && vecmax(digits(n^2))==6
CROSSREFS
Sequence in context: A327110 A255925 A095623 * A105934 A217256 A179168
KEYWORD
base,nonn
AUTHOR
Felix Fröhlich, Apr 18 2015
EXTENSIONS
Corrected b-file from Felix Fröhlich, Mar 18 2022
STATUS
approved

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Last modified March 28 05:02 EDT 2024. Contains 371235 sequences. (Running on oeis4.)