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Numbers that have the same number of divisors as their digit reversal, but with different prime signatures.
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%I #19 Dec 30 2020 04:11:27

%S 24,42,264,288,462,658,856,882,1071,1128,1314,1464,1701,2058,2130,

%T 2132,2312,2324,2424,2510,2590,2616,2664,2744,2765,2782,2786,2872,

%U 2904,2938,2975,3159,3194,4010,4090,4092,4094,4125,4131,4136,4168,4184,4220,4228

%N Numbers that have the same number of divisors as their digit reversal, but with different prime signatures.

%C Terms in A062895 but not in A085869.

%H Amiram Eldar, <a href="/A087093/b087093.txt">Table of n, a(n) for n = 1..10000</a>

%e 24 and 42 are members as 24 and 42 each have 8 divisors but with different prime signatures.

%t psQ[n_]:=Sort[Transpose[FactorInteger[n]][[2]]]!=Sort[Transpose[ FactorInteger[FromDigits[Reverse[IntegerDigits[n]]]]][[2]]];ndQ[n_]:= DivisorSigma[0,n]==DivisorSigma[0,FromDigits[Reverse[ IntegerDigits[ n]]]]; Select[Range[5000],psQ[#]&&ndQ[#]&] (* _Harvey P. Dale_, Nov 11 2011 *)

%Y Cf. A000005, A062895, A085869, A085870.

%K nonn,base

%O 1,1

%A _Ray Chandler_, Aug 09 2003