OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
FORMULA
Equals 1+2*A096788.
MATHEMATICA
2Select[ Range[ 450], PrimeQ[ # ] == PrimeQ[ # + 1] == False && PrimeQ[2# + 1, GaussianIntegers -> True] == True &] + 1 (* Robert G. Wilson v, Jul 11 2004 *)
Select[Total/@Partition[Select[Range[500], CompositeQ], 2, 1], PrimeQ[#] && IntegerQ[ (#-3)/4]&] (* Harvey P. Dale, Mar 06 2019 *)
PROG
(PARI) nextcomposite(k)=if(k<3, 4, if(isprime(k), k+1, k));
{m=440; n=4; while(n<m, k=nextcomposite(n+1); p=n+k; if(isprime(p)&&(p%4)==3, print1(p, ", ")); n=k)} \\ Klaus Brockhaus, Jul 10 2004
CROSSREFS
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Jul 09 2004
EXTENSIONS
Corrected and extended by Klaus Brockhaus and Ray Chandler, Jul 10 2004
STATUS
approved