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 A127270 #12 Feb 28 2023 03:28:00 %S A127270 19,79,229,271,349,359,373,677,733,743,751,797,937,1231,1279,1459, %T A127270 1489,1549,1733,1789,1801,1973,1979,2069,2539,2693,2777,2791,2837, %U A127270 2857,3061,3083,3191,3329,3557,3559,3659,3691,3719,3919,3929,3989,4129,4283,4447 %N A127270 Primes prime(k) such that the sum of the composites between prime(k) and prime(k+2) is prime. %e A127270 The composites between prime(8) = 19 and prime(10) = 29 are 20, 21, 22, 24, 25, 26, 27, 28. Their sum 193 is prime, hence prime(8) = 19 is a term. %t A127270 Do[p = Prime[n]; If[PrimeQ[Apply[Plus, Select[Table[i, {i, p + 1, Prime[n + 2] - 1}], Not[PrimeQ[ # ]] &]]], Print[p]], {n, 1, 1000}] (* _Michael Taktikos_, Apr 01 2007 *) %o A127270 (Magma) [ p: p in [ NthPrime(k): k in [1..650] ] | IsPrime(&+[ c: c in [p+1..NextPrime(NextPrime(p))-1] ] - NextPrime(p)) ]; /* _Klaus Brockhaus_, Mar 29 2007 */ %K A127270 nonn %O A127270 1,1 %A A127270 _J. M. Bergot_, Mar 27 2007 %E A127270 Edited and extended by _Klaus Brockhaus_, Mar 29 2007