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A153350 Numbers n such that 7n+11 is not prime. 1
1, 2, 3, 4, 5, 7, 9, 10, 11, 12, 13, 15, 16, 17, 19, 21, 22, 23, 25, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 55, 56, 57, 58, 59, 61, 62, 63, 64, 65, 66, 67, 69, 70, 71, 72, 73, 74, 75, 76, 77, 79, 81, 82, 83, 85, 87, 88, 89 (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:

*;

*,2;

*,*,*;

*,*,*,10;

*,*,*,*,*;

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

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

*,*,*,*,*,30,*,*;

*,12,*,*,*,*,*,*,50;

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

*,*,*,28,*,*,*,*,*,*,74;

*,*,*,*,*,*,52,*,*,*,*,*;

10,*,*,*,*,*,*,64,*,*,*,*,*; etc.

where * marks the non-integer values of (4*h*k + 2*k + 2*h - 10)/7 with h >= k >= 1. - Vincenzo Librandi, Jan 17 2013

MATHEMATICA

Select[Range[200], !PrimeQ[7 # + 11] &] (* Vincenzo Librandi, Jan 13 2013 *)

PROG

(PARI) isA153350(n)=!isprime(7*n+11)

(MAGMA) [n: n in [0..150] | not IsPrime(7*n+11)]; // _VIncenzo Librandi_, Jan 13 2013

CROSSREFS

Cf. A101123.

Sequence in context: A039201 A039151 A039110 * A191919 A039055 A047504

Adjacent sequences:  A153347 A153348 A153349 * A153351 A153352 A153353

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 24 2008

EXTENSIONS

Corrected and edited by Michael B. Porter, Apr 20 2010

STATUS

approved

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Last modified March 30 15:48 EDT 2017. Contains 284302 sequences.