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A117755
Squares which remain squares when each digit is replaced by the next digit.
10
0, 9, 25, 2025, 13225, 1974025, 4862025, 6943225, 60415182025, 207612366025, 916408817340025, 9960302475729225, 153668543313582025, 1978088677245614025, 13876266042653742025, 20761288044852366025, 47285734107144405625, 406066810454367265225
OFFSET
1,2
COMMENTS
Replace 1 with 2, 2 with 3, ..., 8 with 9 and 9 with 0.
LINKS
EXAMPLE
13225 is in the sequence because (1) it is a square and (2)if we transform it we get 24336 and this is also a square.
MATHEMATICA
Select[Range[500000]^2, IntegerQ[(FromDigits[((1 + IntegerDigits[ # ]) /. 10-> 0])^1/2 &] (* Harvey P. Dale, Jan 21 2007 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Luc Stevens (lms022(AT)yahoo.com), Apr 14 2006
EXTENSIONS
More terms from Harvey P. Dale, Jan 21 2007
3 more terms from Donovan Johnson, Apr 03 2008
a(14)-a(21) from Max Alekseyev, Oct 22 2008
a(1) = 0 prepended by Max Alekseyev, Jul 26 2023
STATUS
approved