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Non-palindromic numbers k for which d(k) = d(R(k)), where R(k) is the reversal of k and d(k) is the number of divisors of k.
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%I #38 Feb 20 2022 22:52:39

%S 13,15,17,24,26,31,37,39,42,51,58,62,71,73,79,85,93,97,107,113,115,

%T 117,122,123,129,143,149,155,157,158,159,165,167,169,177,178,179,183,

%U 185,187,199,203,205,221,226,246,264,265,285,286,288,294,302,311,314,319

%N Non-palindromic numbers k for which d(k) = d(R(k)), where R(k) is the reversal of k and d(k) is the number of divisors of k.

%H Michael S. Branicky, <a href="/A350867/b350867.txt">Table of n, a(n) for n = 1..10000</a>

%e 264 and 462 are non-palindromic and also d(264) = 16 = d(462), and so both are members.

%o (PARI) isok(k) = my(R = fromdigits(Vecrev(digits(k)))); R != k && numdiv(R) == numdiv(k);

%o (Python)

%o from sympy import divisor_count as d

%o def ok(k): Rk = int(str(k)[::-1]); return Rk != k and d(k) == d(Rk)

%o print([k for k in range(320) if ok(k)]) # _Michael S. Branicky_, Feb 20 2022

%Y Cf. A000005 (d), A004086 (R).

%Y Intersection of A029742 and A062895.

%K base,nonn,easy

%O 1,1

%A _Daniel Tsai_, Feb 18 2022