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A095969 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
4, 6, 12, 25, 27, 29, 48, 63, 88, 93, 134, 147, 149, 151, 153, 181, 211, 224, 235, 247, 249, 285, 301, 389, 433, 483, 612, 642, 694, 742, 877, 975, 994, 1037, 1039, 1080, 1094, 1153, 1276, 1278, 1301, 1380, 1395, 1439, 1474, 1563, 1580, 1617, 1638, 1688 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..50.

EXAMPLE

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.

MATHEMATICA

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 *)

PROG

(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

CROSSREFS

Sequence in context: A162688 A070232 A037100 * A090608 A197467 A256350

Adjacent sequences:  A095966 A095967 A095968 * A095970 A095971 A095972

KEYWORD

nonn

AUTHOR

Ray G. Opao, Jul 15 2004

STATUS

approved

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Last modified January 18 01:10 EST 2022. Contains 350410 sequences. (Running on oeis4.)