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A152070
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Squares which form nonzero squares when their reversal is subtracted from them.
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0
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6300100, 7502121, 16654561, 57942544, 74753316, 696379321, 1185424900, 2176315801, 16960113361, 21735899761, 44504965444, 52141439025, 95610824100, 105593152401, 189565322881, 213454164121, 293481144121, 527475375625
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2) = 2739^2 = 7502121 => 7502121 - 1212057 = 6290064 = 2508^2.
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MATHEMATICA
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nzsQ[n_]:=Module[{c=Sqrt[n-FromDigits[Reverse[IntegerDigits[n]]]]}, c!=0 && IntegerQ[c]]; Select[Range[750000]^2, nzsQ] (* Harvey P. Dale, Aug 03 2013 *)
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PROG
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(PARI) reverse(expr)=my(v=Vec(Str(expr)), n=length(v)); concat(vector(n, i, v[n-i+1])); lista(nn) = {for (n=1, nn, if (issquare(n), rn = eval(reverse(n)); if (n!= rn && issquare(n-rn), print1(n, ", "))); ); } \\ Michel Marcus, Jun 02 2013
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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