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%I #7 Aug 14 2021 18:55:11
%S 4888884,8896888,13345332,74732526,100999899,140732592,179555376,
%T 269130862,295777482,444888444,734059326,880968088,978745768,
%U 1032039008,1183109928,1321452132,1399939992,1548058512,1614785172,1886140256
%N Numbers that have exactly 15 representations as a product of two palindromes.
%e 4888884 is in the sequence since 4888884 = 1*4888884 = 2*2444442 = 4*1222221 = 11*444444 = 22*222222 = 44*111111 = 111*44044 = 121*40404 = 222*22022 = 242*20202 = 444*11011 = 484*10101 = 1001*4884 = 1221*4004 = 2002*2442.
%t f[n_]:=f[n]=Length[Select[Divisors[n],#<=n^(1/2)&&FromDigits[ Reverse[IntegerDigits[ # ]]]==#&&FromDigits[Reverse[IntegerDigits [n/# ]]]==n/#&]];Do[If[f[n]==15,Print[n]],{n,125000000}]
%Y Cf. A002113, A116993, A125832, A125833, A125835.
%K base,nonn
%O 1,1
%A _Farideh Firoozbakht_, Dec 11 2006
%E a(6)-a(20) from _Donovan Johnson_, Aug 05 2009
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