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A153403
Numbers n such that 10*n+3 is not prime.
1
3, 6, 9, 12, 13, 14, 15, 18, 20, 21, 24, 25, 27, 30, 32, 33, 34, 36, 39, 40, 41, 42, 45, 47, 48, 49, 51, 53, 54, 55, 57, 58, 60, 62, 63, 66, 69, 70, 71, 72, 75, 76, 78, 79, 80, 81, 83, 84, 87, 89, 90, 91, 92, 93, 94, 96, 97, 99, 100
OFFSET
1,1
LINKS
EXAMPLE
Distribution of the terms in the following triangular array:
*;
*,*;
*,*,*;
*,*,6,*;
3,*,*,*,*;
*,*,*,*,14,*;
*,*,*,*,*,*,*;
*,*,*,15,*,*,*,*;
*,*,13,*,*,*,*,32,*;
6,*,*,*,*,27,*,*,*,*;
*,*,*,*,25,*,*,*,*,48,*; etc.
where * marks the non-integer values of (2*h*k + k + h - 1)/5 with n >= k >= 1. - Vincenzo Librandi, Jan 14 2013
MATHEMATICA
lst={}; Do[p=10*n+3; If[ !PrimeQ[p], AppendTo[lst, n]], {n, 0, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, May 12 2010 *)
PROG
(Magma) [n: n in [0..150] | not IsPrime(10*n + 3)]; // Vincenzo Librandi, Jan 14 2013
CROSSREFS
Cf. A102338.
Sequence in context: A329517 A297567 A285402 * A336341 A376045 A257220
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 25 2008
STATUS
approved