

A186243


Numbers n such that 6n5 and 6n1 are both primes.


8



2, 3, 4, 7, 8, 12, 14, 17, 18, 19, 22, 28, 33, 38, 39, 47, 52, 53, 59, 64, 67, 74, 77, 78, 82, 84, 103, 108, 113, 124, 127, 129, 138, 143, 144, 147, 148, 152, 157, 162, 169, 182, 183, 203, 214, 217, 218, 238, 239, 242, 248, 249, 259, 262, 264, 267, 269
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OFFSET

1,1


COMMENTS

Numbers n such that 6n5 and 6n1 are cousin primes. The D = 2 numbers in class II, from page 3 of Weber.  Jonathan Vos Post, Feb 14 2011


LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000
H. J. Weber, Exceptional Prime Number Twins, Triplets and Multiplets, arXiv:1102.3075 [math.NT], 2011.
Eric W. Weisstein, Cousin Primes.


FORMULA

{n such that 6*n5 is in A023200} = {n such that 6*n1 is in A046132}.


EXAMPLE

a(3) = 4 because 6*45 = 19 is prime, and 6*41 = 23 is prime.


MATHEMATICA

Select[Range[400], PrimeQ[6#5] && PrimeQ[6#1] &] (* Alonso del Arte, Feb 16 2011 *)


CROSSREFS

Cf. A023200, A046132, A088765.
Sequence in context: A078662 A050048 A122456 * A073882 A015840 A051213
Adjacent sequences: A186240 A186241 A186242 * A186244 A186245 A186246


KEYWORD

nonn,easy


AUTHOR

Jonathan Vos Post, Feb 15 2011


STATUS

approved



