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 A307882 #15 May 08 2019 15:57:08 %S A307882 -1,1,3,5,7,9,11,13,15,25,29,31,39,45,61,63,75,81,85,111,123,131,151, %T A307882 175,207,225,241,267,301,329,335,427,435,505,539,565,611,617,665,695, %U A307882 739,805,843,875,1113,1143,1465,1797,1801,1959,2065,2369,2783 %N A307882 Records of the offset k in A307881, divided by 3. %C A307882 The divisibility of k by 3 of all terms after a(1) is conjectural. Offsets not divisible by 3 are given as -k instead of k/3. %o A307882 (PARI) kmax=0; for(n=2,10^7,forstep(k=1,n,2,if(isprime(2*n-k)&&isprime(2*n+k),if(k>kmax,if(k%3!=0,print1(-k,", "),print1(k/3,", "));kmax=k);break(1)))) %Y A307882 Cf. A065978, A293858, A307881, A325142. %K A307882 sign,more %O A307882 1,3 %A A307882 _Hugo Pfoertner_, May 03 2019