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%I #15 May 08 2019 15:57:08
%S -1,1,3,5,7,9,11,13,15,25,29,31,39,45,61,63,75,81,85,111,123,131,151,
%T 175,207,225,241,267,301,329,335,427,435,505,539,565,611,617,665,695,
%U 739,805,843,875,1113,1143,1465,1797,1801,1959,2065,2369,2783
%N Records of the offset k in A307881, divided by 3.
%C 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 (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 Cf. A065978, A293858, A307881, A325142.
%K sign,more
%O 1,3
%A _Hugo Pfoertner_, May 03 2019