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 A235646 #62 Feb 02 2017 00:25:41 %S A235646 43,1429,2239,3319,4831,6379,8821,10501,11383,12781,13003,14771,15091, %T A235646 16063,16759,18223,19213,19681,20021,22571,24103,24109,24571,25939, %U A235646 27271,28933,29833,30241,31723,33679,33811,34381,34781,35591,35863,39373 %N A235646 Primes p such that b=2*p+1 is semiprime, c=2*b+1 is 3-almost prime and d=2*c+1 is 4-almost prime. %H A235646 Vincenzo Librandi, <a href="/A235646/b235646.txt">Table of n, a(n) for n = 1..1000</a> %e A235646 p = 43, b = 87 = 2*29 = A001358(30), c = 175 = 5*5*7 = A014612(43), d = 351 = 3*3*3**13 = A014613(50). %t A235646 Select[ Prime@ Range@ 4200,PrimeOmega[2#+1]==2 && PrimeOmega[4#+3]==3 && PrimeOmega[8#+7]==4 &] (* _Robert G. Wilson v_, Feb 22 2014 *) %o A235646 (PARI) forprime(p=43,40000,if(bigomega(a=2*p+1)==2&& bigomega(b=2*c+1)==3&&bigomega(c=2*d+1)==4,print(p","))) %Y A235646 Subsequence of A238202. %Y A235646 Cf. A000040, A001358, A014612, A014613, A234095. %K A235646 nonn %O A235646 1,1 %A A235646 _Zak Seidov_, Feb 20 2014