This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A263106 #15 Jul 23 2023 01:54:07 %S A263106 4,6,9,15,22,26,33,39,49,51,55,58,62,77,85,93,94,111,122,129,134,141, %T A263106 145,155,158,159,161,177,178,183,185,187,202,206,214,226,254,262,298, %U A263106 303,309,314,321,339,341,355,358,362,371,381,391,393,394,403,407,413 %N A263106 Semiprimes such that the leftward cyclic permutation of its decimal digits is also semiprime. %C A263106 First 18 terms are also in A085751. %H A263106 Zak Seidov, <a href="/A263106/b263106.txt">Table of n, a(n) for n = 1..65049</a> (all terms up to 10^6) %e A263106 15 = 3 * 5, 51 = 3 * 17; 889 = 7 * 17, 898 = 2 * 449. %t A263106 Select[Range[4, 1000], 2 == PrimeOmega[#] == PrimeOmega[FromDigits[RotateLeft[IntegerDigits[#]]]] &] %o A263106 (PARI) shl(n)=if(n<10,return(n)); my(d=digits(n)); fromdigits(concat(d[2..#d], d[1])) %o A263106 is(n)=bigomega(n)==2 && bigomega(shl(n))==2 \\ _Charles R Greathouse IV_, Oct 12 2015 %Y A263106 Cf. A001292, A001358, A085751. %K A263106 nonn,base %O A263106 1,1 %A A263106 _Zak Seidov_, Oct 09 2015