OFFSET
1,2
COMMENTS
Conjecture: There are infinitely many primes not of the form a(i)+a(j). - David W. Wilson, Apr 14 2003
Are there infinitely many even numbers in the sequence? - David W. Wilson, Apr 14 2003
LINKS
Jinyuan Wang, Table of n, a(n) for n = 1..1000
MATHEMATICA
a[1]=1; p[1]={2}; a[n_] := Module[{k, new}, For[k=a[n-1]+1, Intersection[p[n-1], (new=Select[(a/@Range[n-1])+k, PrimeQ])]!={}, k++, Null]; p[n]=Union[p[n-1], new]; a[n]=k];
PROG
(PARI) v=vector(1000); print1(v[1]=1, ", "); vv=vector(1000); vv[1]=1; n=1; while(n<100, n=n+1; for(m=1, 10^9, f=0; if(!vv[m], v[n]=m; w=vector(1000); for(k=2, n, for(l=1, k-1, s=v[k]+v[l]; if(isprime(s), if(w[s], f=1; break, w[s]=1))); if(f, break)); if(!f, print1(m, ", "); vv[m]=1; break))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Feb 20 2003
EXTENSIONS
Corrected and extended by Ralf Stephan, Apr 14 2003
STATUS
approved