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A086498 Rearrangement of primes such that every (2n)-th partial sum is a prime. Every (2n+1)-st term is the smallest prime which has not been included earlier.

%I A086498 #9 Aug 05 2020 02:01:01
%S A086498 2,3,5,7,11,13,17,31,19,23,29,37,41,43,47,61,53,67,59,73,71,97,79,83,
%T A086498 89,103,101,109,107,127,113,151,131,139,137,163,149,199,157,173,167,
%U A086498 181,179,271,191,229,193,257,197,277,211,239,223,263,227,313,233,241,251
%N A086498 Rearrangement of primes such that every (2n)-th partial sum is a prime. Every (2n+1)-st term is the smallest prime which has not been included earlier.
%H A086498 Robert Israel, <a href="/A086498/b086498.txt">Table of n, a(n) for n = 1..10000</a>
%p A086498 N:= 100: # to get all terms before the first term > Prime(N).
%p A086498 Primes:= [seq(ithprime(i),i=2..N)]: nP:= N-1: S:= 2: R:= 2:
%p A086498 do
%p A086498   found:= false;
%p A086498   for j from 1 to nP do
%p A086498     if isprime(S+Primes[j]) then
%p A086498       R:= R, Primes[j];
%p A086498       S:= S + Primes[j];
%p A086498       Primes:= subsop(j=NULL, Primes);
%p A086498       nP:= nP-1;
%p A086498       found:= true;
%p A086498       break
%p A086498     fi
%p A086498   od;
%p A086498   if not found or nP = 0 then break fi;
%p A086498   R:= R, Primes[1];
%p A086498   S:= S + Primes[1];
%p A086498   Primes:= Primes[2..-1];
%p A086498   nP:= nP-1;
%p A086498 od:
%p A086498 R; # _Robert Israel_, Aug 04 2020
%Y A086498 Cf. A086496, A086497, A096499.
%K A086498 nonn
%O A086498 1,1
%A A086498 _Amarnath Murthy_, Jul 28 2003
%E A086498 More terms from _Ray Chandler_, Sep 17 2003