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A030097 Numbers k such that k^2 has only even digits. 3
0, 2, 8, 20, 22, 68, 78, 80, 92, 162, 168, 200, 202, 220, 262, 298, 478, 492, 498, 668, 680, 780, 800, 898, 908, 920, 932, 1422, 1492, 1498, 1620, 1680, 1692, 2000, 2002, 2020, 2022, 2192, 2200, 2202, 2498, 2502, 2578, 2620, 2832, 2878, 2978, 2980, 4502 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A136904 is a subsequence. - Zak Seidov, Dec 03 2012
LINKS
FORMULA
a(n) = sqrt(A030098(n)). - Zak Seidov, Dec 03 2012
MATHEMATICA
Select[ Range[ 3000 ], Union[ EvenQ[ IntegerDigits[ #^2 ] ] ] == {True} & ]
PROG
(PARI) is_A030097(n)=!setminus(Set(Vec(Str(n^2))), Vec("02468")) \\ M. F. Hasler, Dec 13 2011
CROSSREFS
Sequence in context: A227127 A227399 A327098 * A136904 A043002 A108180
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
More terms from Zak Seidov, May 24 2010
STATUS
approved

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Last modified March 3 00:46 EST 2024. Contains 370499 sequences. (Running on oeis4.)