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Numbers k such that least prime in the Goldbach partition of k increases.
13

%I #28 May 17 2021 21:11:04

%S 4,6,12,30,98,220,308,556,992,2642,5372,7426,43532,54244,63274,113672,

%T 128168,194428,194470,413572,503222,1077422,3526958,3807404,10759922,

%U 24106882,27789878,37998938,60119912,113632822,187852862,335070838

%N Numbers k such that least prime in the Goldbach partition of k increases.

%H Charles R Greathouse IV, <a href="/A025018/b025018.txt">Table of n, a(n) for n = 1..69</a> (from Tomás Oliveira e Silva)

%H Mark A. Herkommer, <a href="http://www.herkommer.org/goldbach/goldbach.htm">Goldbach Conjecture Research</a>

%H Jorg Richstein, <a href="http://www.ams.org/journals/mcom/2001-70-236/S0025-5718-00-01290-4/S0025-5718-00-01290-4.pdf">Verifying Goldbach's Conjecture up to 4 * 10^14</a>, Math. of Computation, Vol. 70, No. 236, pp. 1745-1749 (July 2000)

%H <a href="/index/Go#Goldbach">Index entries for sequences related to Goldbach conjecture</a>

%H Tomás Oliveira e Silva, <a href="http://sweet.ua.pt/tos/goldbach.html">Goldbach conjecture verification</a>

%t p = 1; r = {}; Do[ k = 2; While[ !PrimeQ[k] || !PrimeQ[2n - k], k++ ]; If[k > p, p = k; r = Append[r, 2n]], {n, 2, 10^8}]; r

%o (PARI) Gold(n)=forprime(p=2,min(n\2,default(primelimit)),if(isprime(n-p),return(p)))

%o r=0;forstep(n=4,1e6,2,t=Gold(n);if(t>r,r=t;print1(n", "))) \\ _Charles R Greathouse IV_, Feb 21 2012

%Y Cf. A001172, A025019.

%K nonn,nice

%O 1,1

%A _David W. Wilson_

%E Edited and extended by _Robert G. Wilson v_, Dec 13 2002