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A030097 Numbers n such that n^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

Zak Seidov, Table of n, a(n) for n = 1..2000

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

Cf. A030098, A136904.

Sequence in context: A188893 A227127 A227399 * A136904 A043002 A108180

Adjacent sequences:  A030094 A030095 A030096 * A030098 A030099 A030100

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

EXTENSIONS

More terms from Zak Seidov, May 24 2010

STATUS

approved

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Last modified May 28 17:57 EDT 2017. Contains 287241 sequences.