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A155941 Numbers n such that 16*n+1 is not prime. 3
0, 2, 3, 4, 5, 8, 9, 10, 11, 13, 14, 17, 18, 19, 20, 23, 24, 26, 29, 30, 31, 32, 33, 34, 35, 38, 39, 41, 43, 44, 45, 46, 47, 49, 50, 51, 52, 53, 54, 56, 57, 59, 60, 62, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 77, 79, 80, 82, 83, 84, 86, 87, 89, 90, 91, 92, 94, 95 (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 a(n)>0 in the following triangular array:

*;

*,*;

*,*,3;

*,*,*,5;

2,*,*,*,*;

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

*,*,*,*,*,*,14;

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

*,*,*,*,13,*,*,*,*;

*,*,*,*,*,17,*,*,*,*;

*,*,10,*,*,*,*,*,*,*,33;

*,*,*,14,*,*,*,*,*,*,*,39;

5,*,*,*,*,*,*,*,32,*,*,*,*; etc.

where * marks the non-integer values of (2*h*k + k + h)/8 with h >= k >= 1. - Vincenzo Librandi, Jan 15 2013

MATHEMATICA

Select[Range[0, 100], !PrimeQ[16 # + 1] &] (* Vincenzo Librandi, Oct 15 2012 *)

PROG

(MAGMA) [n: n in [0..100] |not IsPrime(16*n+1)]; // Vincenzo Librandi, Oct 15 2012

CROSSREFS

Cf. A094407, A155942, A155943.

Sequence in context: A031482 A047369 A004827 * A046892 A068406 A276878

Adjacent sequences:  A155938 A155939 A155940 * A155942 A155943 A155944

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Jan 31 2009

EXTENSIONS

0 added by Arkadiusz Wesolowski, Aug 03 2011

STATUS

approved

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Last modified February 17 17:59 EST 2020. Contains 331999 sequences. (Running on oeis4.)