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 A175893 #12 Apr 05 2025 14:53:08
%S A175893 1,2,3,6,7,8,10,17,22,27,29,30,35,45,48,49,50,52,53,57,61,68,70,80,81,
%T A175893 85,94,104,106,117,120,125,126,127,131,132,136,137,138,143,146,156,
%U A175893 157,166,177,191,198,206,220,223,224,225,233,236,244,248,254,259,261,262
%N A175893 Numbers m such that 2*prime(m)+prime(m+1) is prime.
%H A175893 Harvey P. Dale, <a href="/A175893/b175893.txt">Table of n, a(n) for n = 1..1000</a>
%F A175893 a(n) = pi(A173971(n))=A000720(A173971(n)).
%t A175893 Select[Range[300],PrimeQ[2Prime[#]+Prime[#+1]]&] (* _Harvey P. Dale_, Apr 05 2025 *)
%o A175893 (PARI) {my(a=2);for(n=1,1000,my(b=nextprime(a+1));isprime(2*a+b)&print1(n,", ");a=b)}
%Y A175893 Cf. A000040 The prime numbers.
%Y A175893 A173971 Primes p such that 2*p+NextPrime are prime numbers.
%Y A175893 A000720 pi(n), the number of primes <= n.
%K A175893 easy,nonn
%O A175893 1,2
%A A175893 _Zak Seidov_, Oct 10 2010