A357934 - OEIS

%I #17 Oct 21 2022 14:43:57

%S 15,33,51,55,85,87,123,145,177,187,205,213,295,303,319,321,355,411,

%T 447,451,493,505,535,537,573,591,649,681,685,697,717,745,781,807,843,

%U 895,933,955,985,1003,1041,1111,1135,1177,1189,1195,1207,1257,1293,1345,1383,1405,1507,1555,1563

%N Products of two distinct lesser twin primes A001359.

%t d = {};less = Select[Range[1607], PrimeQ[#] && PrimeQ[# + 2] &];Do[Do[AppendTo[d, less[[m]] less[[n]]], {m, n + 1, Length[less]}], {n,

%t   1, Length[less] - 1}]; Take[Sort[d], 55]

%o (PARI) list(lim)=my(v=List(),p=5); forprime(q=7,lim\3+2, if(q-p==2, my(r=3); forprime(s=5,min(lim\p+2,p), if(s-r==2, listput(v, p*r)); r=s)); p=q); Set(v) \\ _Charles R Greathouse IV_, Oct 21 2022

%Y Cf. A001359.

%K nonn

%O 1,1

%A _Artur Jasinski_, Oct 21 2022