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%I #10 Mar 02 2015 02:25:24
%S 1,2,3,4,5,6,7,8,9,10,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,
%T 28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,
%U 51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73
%N A101909 sorted and duplicates removed.
%H Charles R Greathouse IV, <a href="/A101947/b101947.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) bet2n4n(n) = { local(c,c1,x,y); a=vector(5001); for(x=1,n, c=0; forprime(y=2*x+1,4*x-1, c++; ); a[x] = c; ); b=vecsort(a); for(x=1,5000, if(b[x]>0, if(b[x]<>b[x+1],print1(b[x]",") ) ); ) }
%o (PARI) s=0;v=vectorsmall(10^6,n,s+=isprime(4*n-1)+isprime(4*n-3)-isprime(2*n-1));v=vecsort(v,,8);vecextract(v,Str("1..",#v\2)) \\ _Charles R Greathouse IV_, Mar 12 2012
%Y Cf. A101909, A101983-A101985.
%K easy,nonn
%O 1,2
%A _Cino Hilliard_, Jan 28 2005
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