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A153381 Numbers n such that 11*n+5 is not prime. 1
1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 35, 37, 38, 39, 40, 41, 43, 44, 45, 46, 47, 48, 49, 50, 51, 53, 55, 56, 57, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 79, 80, 81, 83, 85, 86, 87, 88 (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 even terms in the following triangular array:

*;

*,*;

*,*,4;

2,*,*,*;

*,*,*,*,*;

*,*,*,*,*,*;

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

*,*,*,*,*,*,*,*,;

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

*,*,*,*,*,*,*,32,*,*;

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

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

*,*,*,*,*,*,*,*,*,*,56,*,*:

*,*,18,*,*,*,*,*,*,*,*,*,*,76;

8,*,*,*,*,*,*,*,*,*,*,70,*,*,*; etc.

where * marks the non-integer values of (4*h*k + 2*k + 2*h - 4)/11 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013

MATHEMATICA

Select[Range[0, 200], !PrimeQ[11 # + 5] &] (* Vincenzo Librandi, Jan 13 2013 *)

PROG

(MAGMA) [n: n in [0..150] | not IsPrime(11*n+5)]; // Vincenzo Librandi, Jan 13 2013

CROSSREFS

Cf. A108233.

Sequence in context: A049093 A098901 A098767 * A091010 A116358 A060683

Adjacent sequences:  A153378 A153379 A153380 * A153382 A153383 A153384

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 25 2008

EXTENSIONS

Erroneous comment deleted by N. J. A. Sloane, Jun 23 2010

STATUS

approved

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Last modified September 24 18:54 EDT 2017. Contains 292433 sequences.