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A153307 Numbers n such that 14*n+3 is not prime. 1
3, 6, 8, 9, 10, 12, 13, 15, 18, 21, 23, 24, 27, 28, 30, 31, 32, 33, 35, 36, 38, 39, 42, 43, 45, 48, 49, 50, 51, 52, 53, 54, 57, 58, 60, 62, 63, 64, 65, 66, 68, 69, 72, 73, 75, 76, 77, 78, 81, 83, 84, 86, 87, 88, 90 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

Distribution of the terms in the following triangular array:

*;

*,*;

*,*,*;

*,3,*,*;

*,*,*,*,*;

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

3,*,*,*,*,*,*;

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

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

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

*,8,*,*,*,*,*,*,31,*,*;

*,*,*,*,*,23,*,*,*,*,*;

*,*,*,*,21,*,*,*,*,*,*,48,*;etc.

where * marks the non-integer values of (2*h*k + k + h - 1)/7 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013

MATHEMATICA

Select[Range[0, 200], !PrimeQ[14*# + 3]&] (* Vincenzo Librandi, Jan 12 2013 *)

PROG

(MAGMA) [n: n in [0..150] | not IsPrime(14*n + 3)]; // Vincenzo Librandi, Jan 12 2013

CROSSREFS

A090614.

Sequence in context: A188544 A163463 A137386 * A265227 A201817 A004715

Adjacent sequences:  A153304 A153305 A153306 * A153308 A153309 A153310

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 23 2008

STATUS

approved

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Last modified November 22 15:27 EST 2017. Contains 295089 sequences.