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A115669
Numbers the reversal of whose square is a brilliant number (A078972).
3
2, 3, 11, 13, 20, 30, 31, 59, 61, 101, 110, 112, 113, 128, 130, 131, 178, 200, 300, 301, 307, 310, 311, 388, 590, 599, 610, 839, 854, 875, 949, 989, 1003, 1010, 1021, 1031, 1100, 1102, 1103, 1105, 1112, 1120, 1124, 1130, 1175, 1201, 1216, 1280, 1300
OFFSET
1,1
LINKS
EXAMPLE
3481=59^2 is a square and 1843=19*97 is brilliant.
MATHEMATICA
sbnQ[n_]:=Module[{fi=FactorInteger[IntegerReverse[n^2]]}, (Length[fi]==1 && fi[[1, 2]]==2)||(Length[fi]==2&&fi[[All, 2]]=={1, 1})&&Length[Union[ IntegerLength[ fi[[All, 1]]]]]==1]; Select[Range[1300], sbnQ] (* Harvey P. Dale, Mar 23 2018 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Jan 31 2006
STATUS
approved