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A175823
Numbers n such that gcd(n^2, reverse(n^2)) = n
0
1, 9, 297, 513, 783, 999, 1323, 1331, 4961, 10989, 11979, 12969, 14733, 20402, 29088, 89109, 99999, 109989, 122221, 188887, 210789, 218097, 377199, 477773, 483516, 525503, 718189, 1099989, 2128806, 2920819
OFFSET
1,2
EXAMPLE
297 is in the sequence, because 297^2 = 88209, and reverse(88209)=90288 = 297*304
MATHEMATICA
Select[Range[5000000], GCD[FromDigits[Reverse[IntegerDigits[(#)^2 ]]], #^2]==# &]
CROSSREFS
Sequence in context: A332129 A086699 A027834 * A129934 A003303 A371252
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Sep 13 2010
STATUS
approved