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If p(k) is the k-th prime, then the n-th set of 2 consecutive cousin prime pairs starts at p(a(n)).
1

%I #6 Sep 08 2022 08:45:14

%S 4,6,12,25,27,29,48,63,88,93,134,147,149,151,153,181,211,224,235,247,

%T 249,285,301,389,433,483,612,642,694,742,877,975,994,1037,1039,1080,

%U 1094,1153,1276,1278,1301,1380,1395,1439,1474,1563,1580,1617,1638,1688

%N If p(k) is the k-th prime, then the n-th set of 2 consecutive cousin prime pairs starts at p(a(n)).

%e a(2)=6: p(6)=13 and p(7)=17, the first cousin prime pair, p(8)=19 and p(9)=23, the second cousin prime pair.

%t n=0 Do[If[Prime[k + 1] - Prime[k]==4&&Prime[k + 3] - Prime[k + 2]==4, n = n + 1; Print[n, " ", k]], {k, 1, 1700}] (* _Vincenzo Librandi_, Jul 03 2015 *)

%o (Magma) [n: n in [1..2000] | NthPrime(n+1)-NthPrime(n) eq 4 and NthPrime(n+3)-NthPrime(n+2) eq 4]; // _Vincenzo Librandi_, Jul 03 2015

%K nonn

%O 1,1

%A _Ray G. Opao_, Jul 15 2004