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 A271982 #16 Nov 01 2024 20:45:21 %S A271982 5,11,17,19,29,31,37,41,47,59,61,67,71,89,97,107,109,131,137,139,149, %T A271982 151,157,181,191,197,199,227,229,239,241,251,269,271,307,311,317,331, %U A271982 337,347,359,367,379,389,397,401,419,421,449,457,461 %N A271982 Primes p such that p + 42 is also prime. %C A271982 A134120 is a subsequence of this sequence. %H A271982 Karl V. Keller, Jr., <a href="/A271982/b271982.txt">Table of n, a(n) for n = 1..10000</a> %e A271982 5 is a term because 5 + 42 = 47 is also prime. %e A271982 11 is a term because 11 + 42 = 53 is also prime. %p A271982 A271982:=n->`if`(isprime(n) and isprime(n+42), n, NULL): seq(A271982(n), n=1..10^3); # _Wesley Ivan Hurt_, Feb 12 2017 %t A271982 Select[Prime@ Range@ 90, PrimeQ[# + 42] &] (* _Michael De Vlieger_, Apr 18 2016 *) %o A271982 (Python) %o A271982 from sympy import isprime %o A271982 for i in range(3,2001,2): %o A271982 if isprime(i) and isprime(i+42): print (i,end=', ') %o A271982 (PARI) lista(nn) = forprime(p=2, nn, if (isprime(p+42), print1(p, ", "))); \\ _Michel Marcus_, Apr 19 2016 %Y A271982 Cf. A000040, A134120. %K A271982 nonn %O A271982 1,1 %A A271982 _Karl V. Keller, Jr._, Apr 17 2016