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 A176807 #8 Feb 06 2019 02:14:19
%S A176807 3,107,137,179,239,419,461,659,1049,1091,1697,1787,1871,2027,2111,
%T A176807 2381,2687,2711,3167,3299,3329,3359,3371,3467,3851,4259,4721,4967,
%U A176807 5279,5501,5639,5651,5867,6269,6449,7487,8819,8969,9011,9431,9629
%N A176807 Lesser of twin primes p such that p = semiprime(k)/3 and p + 2 = semiprime(k+3)/3 for some integer k.
%e A176807 3 is a term because 3 = semiprime(3)/3 = 9/3 and 3 + 2 = 5 = semiprime(3+3)/3 = 15/3.
%p A176807 From _R. J. Mathar_, Apr 27 2010: (Start)
%p A176807 isA001358 := proc(n) numtheory[bigomega](n) = 2 ; end proc:
%p A176807 A001358 := proc(n) option remember ; if n = 1 then 4; else for a from procname(n-1)+1 do if isA001358(a) then return a; end if; end do: end if ; end proc:
%p A176807 A174956 := proc(p) option remember ; for n from 1 do if A001358(n) = p then return n; elif A001358(n) > p then return 0 ; end if; end do: end proc:
%p A176807 A001359 := proc(n) option remember; if n = 1 then 3; else for a from procname(n-1)+2 by 2 do if isprime(a) and isprime(a+2) then return a; end if; end do: end if; end proc:
%p A176807 for i from 1 to 200 do p := A001359(i) ; n := A174956(3*p) ; n3 := A174956(3*p+6) ; if n > 0 and n3 >0 and n3=n+3 then printf("%d,",p) ; end if; end do: (End)
%K A176807 nonn
%O A176807 1,1
%A A176807 _Juri-Stepan Gerasimov_, Apr 26 2010
%E A176807 Corrected (659 inserted, 1031 removed, 2027 inserted) and extended by _R. J. Mathar_, Apr 27 2010