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A257123
Numbers n such that the decimal expansions of both n and n^2 have 2 as smallest digit and 7 as largest digit.
10
275, 2574, 2725, 2765, 4762, 5725, 6762, 7244, 7262, 23765, 25744, 27244, 27325, 27434, 27465, 27525, 27632, 27665, 47725, 52275, 52376, 52475, 52576, 52675, 57242, 67426, 72266, 72275, 72424, 72426, 72576, 72624, 73325, 73725, 74326, 75725, 233725, 233744
OFFSET
1,1
LINKS
PROG
(PARI) is(n) = vecmin(digits(n))==2 && vecmin(digits(n^2))==2 && vecmax(digits(n))==7 && vecmax(digits(n^2))==7
KEYWORD
nonn,base
AUTHOR
Felix Fröhlich, Apr 25 2015
STATUS
approved