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%I #12 Jul 16 2015 21:43:53
%S 15,26,39,49,51,58,62,85,93,94,115,117,122,123,126,129,143,147,155,
%T 158,159,165,169,177,178,183,185,187,203,205,221,225,226,244,246,265,
%U 285,286,289,294,302,314,315,319,321,326,327,329,335,338,339,341,355,366
%N Nonprime numbers n such that n and n-reversed (<> n and no leading zeros) have the same number of prime factors (counted with multiplicity).
%H Nathaniel Johnston, <a href="/A050699/b050699.txt">Table of n, a(n) for n = 1..10000</a>
%e E.g., 321 = 3*107 and 123 = 3*41 -> both 321 and 123 have two prime factors.
%p with(numtheory): read(transforms): for n from 12 to 366 do r:=digrev(n): if(not isprime(n) and not n=r and not n mod 10 = 0 and bigomega(n)=bigomega(r))then printf("%d, ", n); fi: od: # _Nathaniel Johnston_, Jun 23 2011
%t nrnQ[n_]:=Module[{idn=IntegerDigits[n],rev},rev=Reverse[idn];!PrimeQ[n] &&First[rev]!=0&&idn!=rev&&PrimeOmega[n]==PrimeOmega[FromDigits[rev]]]; Select[Range[400],nrnQ] (* _Harvey P. Dale_, Jun 23 2011 *)
%Y Cf. A050700, A050701, A050702, A006567, A097393, A109018-A109031.
%K nonn,base,easy
%O 1,1
%A _Patrick De Geest_, Aug 15 1999
%E Definition clarified by _Harvey P. Dale_, Jun 23 2011
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