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A153327 Numbers n such that 16*n+5 is not prime. 1
1, 4, 5, 7, 8, 10, 13, 15, 16, 19, 20, 21, 22, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 39, 40, 43, 45, 46, 49, 50, 52, 54, 55, 56, 57, 58, 59, 60, 61, 64, 65, 67, 70, 71, 72, 73, 74, 75, 76, 78, 79, 80, 82, 83, 84, 85, 87, 88, 90, 91, 92, 94, 95, 96, 97, 98, 99, 100 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

EXAMPLE

Distribution of the terms in the following triangular array:

*;

*,*;

1,*,*;

*,*,*,*;

*,*,*,*,*,;

*,*,*,7,*,*;

*,*,*,*,10,*,*;

*,5,*,*,*,*,*,*;

*,*,8,*,*,*,*,*,*;

*,*,*,*,*,*,*,22,*,*;

4,*,*,*,*,*,*,*,27*,*;

*,*,*,*,*,20,*,*,*,*,*,*;

*,*,*,*,*,*,25,*,*,*,*,*,*; etc.

where * marks the non-integer values of (2*h*k + k + h - 2)/8 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013

MATHEMATICA

Select[Range[100], !PrimeQ[16# + 5]&] (* Harvey P. Dale, Oct 03 2011 *)

PROG

(MAGMA) [n: n in [0..150] | not IsPrime(16*n + 5)]; // Vincenzo Librandi, Jan 12 2013

CROSSREFS

Cf. A127590.

Sequence in context: A219115 A118731 A076203 * A189707 A120163 A088763

Adjacent sequences:  A153324 A153325 A153326 * A153328 A153329 A153330

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 23 2008

STATUS

approved

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Last modified March 30 12:10 EDT 2020. Contains 333125 sequences. (Running on oeis4.)