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%I #3 Mar 30 2012 17:27:41
%S 2,3,13,5,7,11,19,17,23,29,37,31,41,43,47,59,53,61,67,71,73,79,83,89,
%T 107,97,101,103,109,113,127,131,137,139,149,151,157,163,167,173,179,
%U 181,199,191,193,197,211,223,227,233,229,239,251,241,257,269,263,271,277
%N a(n) = abs(A085401(n-1) - A085401(n)).
%C Primes used in constructing the terms of A085401. Except for an initial part of the sequence and occasional local rearrangements later on (e.g. 199,191,193,197; 1063,1049,1051,1061) the primes appear in ascending order.
%e a(8) = abs(A085401(7) - A085401(8)) = abs(37 - 20) = 17.
%o (PARI) {in(n,v)=local(j,s,b); j=1; s=matsize(v)[2]; b=1; while(b&&j<=s,if(n==v[j],b=0,j++)); !b}
%o {a=1; v=[]; for(n=1,60,p=2; t=1; while(t>0,if(in(p,v),p=nextprime(p+1),if(!isprime(2*a+p),t=0; b=a+p,if(p<a&&!isprime(2*a-p),t=0; b=a-p,p=nextprime(p+1))))); v=concat(v,p); print1(p,","); a=b)}
%Y Cf. A085401, A085400.
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Jun 28 2003
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