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A228358 Numbers n such that 3*n - 4 is not prime. 2
1, 4, 6, 8, 10, 12, 13, 14, 16, 18, 20, 22, 23, 24, 26, 27, 28, 30, 32, 33, 34, 36, 38, 40, 41, 42, 43, 44, 46, 48, 49, 50, 52, 53, 54, 55, 56, 58, 60, 62, 63, 64, 66, 68, 69, 70, 71, 72, 73, 74, 75, 76, 78, 80, 82, 83, 84, 86, 88, 90, 92, 93, 94, 96, 97, 98, 100, 101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

After 1, all terms are given by A153170 +2. [Bruno Berselli, Aug 21 2013]

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

8 is in the sequence since 3*8 - 4 = 20 is not prime.

MATHEMATICA

Select[Range[230], ! PrimeQ[3 # - 4]&]

PROG

(MAGMA) [n: n in [1..120] | not IsPrime(3*n -4)];

CROSSREFS

Cf. A153170, A228121.

Sequence in context: A227405 A061408 A063287 * A134331 A276040 A090334

Adjacent sequences:  A228355 A228356 A228357 * A228359 A228360 A228361

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Aug 21 2013

STATUS

approved

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Last modified October 15 01:40 EDT 2019. Contains 328025 sequences. (Running on oeis4.)