A124379 Numbers n such that 120n-1, 120n+1 are twin primes.

2, 5, 11, 25, 26, 28, 40, 44, 46, 47, 49, 53, 58, 63, 75, 77, 81, 93, 102, 114, 128, 151, 159, 172, 180, 182, 192, 215, 224, 227, 229, 245, 248, 249, 257, 259, 261, 280, 294, 310, 327, 332, 346, 348, 357, 361, 369, 376, 387, 389, 401, 404, 410, 416, 427, 429

Offset

1,1

Comments

20*n's are in A002822 = numbers n such that 6n-1, 6n+1 are twin primes.

Links

Zak Seidov, Table of n, a(n) for n = 1..5746 (Terms < 100000)

Mathematica

Select[Range[500], AllTrue[120#+{-1, 1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Mar 01 2019 *)

Prog

(PARI) isok(n) = isprime(120*n-1) && isprime(120*n+1); \\ Michel Marcus, Oct 11 2013

Crossrefs

Cf. A002822.

Sequence in context: A071879 A228862 A134527 * A302830 A084978 A118036

Adjacent sequences: A124376 A124377 A124378 * A124380 A124381 A124382

Keyword

nonn

Author

Zak Seidov, Oct 28 2006

Status

approved