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 A136903 Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 7. 1

%I

%S 0,2,20,26,200,260,474,2000,2600,2602,4740,4762,20000,20602,26000,

%T 26020,26602,47400,47620,77474,77602,200000,206020,260000,260200,

%U 266020,474000,476200,476474,476662,774740,776020,2000000,2006002,2060200,2060762,2600000,2602000,2647026,2660200,4474674,4740000,4762000,4764740,4766620,7747400

%N Numbers k such that k and k^2 use only the digits 0, 2, 4, 6 and 7.

%C Generated with DrScheme.

%H Jonathan Wellons, <a href="/A136903/b136903.txt">Table of n, a(n) for n = 1..661</a>

%H J. Wellons, <a href="http://jonathanwellons.com/shared-digits/">Tables of Shared Digits</a>

%e 776020464064074^2 = 602207760646220766424777477476.

%t Module[{d={0,2,4,6,7}},Select[FromDigits/@Tuples[d,7],SubsetQ[d,IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, Nov 27 2022 *)

%K base,nonn

%O 1,2

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

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Last modified March 26 02:22 EDT 2023. Contains 361529 sequences. (Running on oeis4.)