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A153236 Numbers n such that 8*n + 3 is not prime. 1
3, 4, 6, 9, 11, 12, 14, 15, 18, 19, 21, 23, 24, 25, 27, 29, 30, 32, 33, 34, 36, 37, 39, 40, 42, 44, 45, 46, 48, 49, 50, 51, 53, 54, 56, 57, 59, 60, 63, 64, 66, 67, 69, 72, 74, 75, 76, 78, 79, 81, 83, 84, 87, 88, 89, 90, 91, 93, 94, 95, 96, 97 (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:

*;

*,*;

*,4,*;

3,*,*,*;

*,*,*,12,*;

*,*,11,*,*,*;

*,9,*,*,*,24,*;

6,*,*,*,23,*,*,*;

*,*,*,21,*,*,*,40,*;

*,*,18,*,*,*,39,*,*,*;

*,14,*,*,*,37,*,*,*,60,*;

9,*,*,*,34,*,*,*,59,*,*,*; etc.

where * marks the non-integer values of (2*h*k + k + h - 1)/4 with h >= k >= 1. - Vincenzo Librandi, Jan 15 2013

MATHEMATICA

Select[Range[0, 200], !PrimeQ[8 # + 3] &] (* Vincenzo Librandi, Jan 12 2013 *)

PROG

(MAGMA) [n: n in [0..110] | not IsPrime(8*n+3)]; // Vincenzo Librandi, Jan 12 2013

CROSSREFS

Cf. A007520, A005124, A139487.

Sequence in context: A284741 A037969 A329862 * A158705 A047415 A087805

Adjacent sequences:  A153233 A153234 A153235 * A153237 A153238 A153239

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 21 2008

STATUS

approved

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Last modified September 21 15:50 EDT 2020. Contains 337272 sequences. (Running on oeis4.)