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A153763 Numbers n such that 8*n+9 is not prime. 1
0, 2, 3, 5, 6, 7, 9, 12, 14, 15, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 30, 32, 33, 35, 36, 37, 39, 40, 42, 44, 45, 46, 47, 48, 51, 52, 54, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 72, 75, 77, 78, 80, 81, 82, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93 (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:

0;

*,2;

*,*,5;

*,*,*,9;

3,*,*,*,14;

*,7,*,*,*,20;

*,*,12,*,*,*,27;

*,*,*,18,*,*,*,35;

6,*,*,*,25,*,*,*,44;

*,12,*,*,*,33,*,*,*,54;

*,*,19,*,*,*,42,*,*,*,65; etc.

where * marks the non-integer values of (2*h*k + k + h - 4)/4 with h >= k >= 1. - Vincenzo Librandi, Jan 14 2013

MATHEMATICA

Select[Range[0, 200], !PrimeQ[8 # + 9] &] (* Vincenzo Librandi, Jan 14 2013 *)

PROG

(MAGMA) [n: n in [0..150] | not IsPrime(8*n+9)]; // Vincenzo Librandi, Jan 14 2013

CROSSREFS

Cf. A153762, A023232.

Sequence in context: A253083 A108130 A195060 * A050747 A261514 A215798

Adjacent sequences:  A153760 A153761 A153762 * A153764 A153765 A153766

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Jan 01 2009

STATUS

approved

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Last modified October 15 18:17 EDT 2019. Contains 328037 sequences. (Running on oeis4.)