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%I #20 Nov 21 2021 07:36:32
%S 14,16,20,30,32,34,35,38,50,70,74,76,91,92,95,98,104,106,110,112,118,
%T 119,124,125,128,130,133,134,136,140,142,145,146,152,160,164,166,170,
%U 172,175,182,188,194,196,200,300,301,305,310,316,320,322,325,328,332
%N Composite numbers which when read backwards are primes.
%C If m is a term, then 10*m is another term. - _Bernard Schott_, Nov 20 2021
%H Michael S. Branicky, <a href="/A076055/b076055.txt">Table of n, a(n) for n = 1..10000</a>
%t Rev[n_]:=FromDigits[Reverse[IntegerDigits[n]]];Select[Range[332],!PrimeQ[#] && PrimeQ[Rev[#]]&] (* _Jayanta Basu_, May 01 2013 *)
%o (Python)
%o from sympy import isprime
%o def ok(n): return not isprime(n) and isprime(int(str(n)[::-1]))
%o print([k for k in range(333) if ok(k)]) # _Michael S. Branicky_, Nov 20 2021
%Y Cf. A076056.
%Y Intersection of A002808 and A095179.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Oct 04 2002
%E Corrected and extended by _Sascha Kurz_, Jan 20 2003
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