A137027 - OEIS

A137027

Numbers k such that k and k^2 use only the digits 1, 3, 4, 6 and 9.

1, 3, 4, 6, 13, 14, 19, 31, 44, 63, 119, 369, 643, 1146, 1414, 1914, 3114, 3364, 4119, 6414, 6646, 11914, 11963, 14119, 31131, 31614, 34196, 36694, 44313, 64313, 64414, 141313, 191414, 311343, 316143, 336696, 363196, 366946, 411636, 411694, 641414, 969119, 1196646, 1414194, 1913469, 3334114, 3363646, 3649196, 3666969, 3693196, 4434114

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OFFSET

1,2

COMMENTS

Generated with DrScheme.

LINKS

Jonathan Wellons, Table of n, a(n) for n = 1..520

J. Wellons, Tables of Shared Digits [archived]

EXAMPLE

641431341949136^2 = 411434166434669436443611146496.

MATHEMATICA

sdQ[n_]:=Module[{idn2=Union[IntegerDigits[n^2]]}, And@@Table[ MemberQ[ {1, 3, 4, 6, 9}, idn2[[i]]], {i, Length[idn2]}]]; Flatten[ Table[ Select[ FromDigits/@Tuples[{1, 3, 4, 6, 9}, d], sdQ], {d, 7}]] (* Harvey P. Dale, Jun 10 2013 *)

CROSSREFS

Sequence in context: A061080 A254049 A280289 * A244409 A102733 A032712

Adjacent sequences: A137024 A137025 A137026 * A137028 A137029 A137030

KEYWORD

base,nonn

AUTHOR

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

STATUS

approved