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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
OFFSET
1,2
LINKS
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
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 24 2008
EXTENSIONS
Corrected and edited by Michael B. Porter, Apr 20 2010
STATUS
approved