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Numbers the reversal of whose square is a brilliant number (A078972).
3

%I #4 Mar 23 2018 12:32:37

%S 2,3,11,13,20,30,31,59,61,101,110,112,113,128,130,131,178,200,300,301,

%T 307,310,311,388,590,599,610,839,854,875,949,989,1003,1010,1021,1031,

%U 1100,1102,1103,1105,1112,1120,1124,1130,1175,1201,1216,1280,1300

%N Numbers the reversal of whose square is a brilliant number (A078972).

%H Harvey P. Dale, <a href="/A115669/b115669.txt">Table of n, a(n) for n = 1..1000</a>

%e 3481=59^2 is a square and 1843=19*97 is brilliant.

%t 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 *)

%Y Cf. A078972, A115667, A115668.

%K nonn,base

%O 1,1

%A _Giovanni Resta_, Jan 31 2006