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A153348 Numbers n such that 16*n+3 is not prime. 1
2, 3, 6, 7, 9, 12, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 27, 28, 30, 32, 33, 36, 37, 38, 39, 42, 44, 45, 47, 48, 50, 51, 52, 53, 54, 56, 57, 58, 60, 61, 62, 63, 64, 65, 66, 67, 69, 71, 72, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 86, 87, 88, 90, 92, 93, 94 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

EXAMPLE

Triangle begins:

*;

*,*;

*,2,*;

*,*,*,*;

*,*,*,6,*;

*,*.*,*,*,*;

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

3,*,*,*,*,*,*,*;

*,*,*,*,*,*,*,20,*;

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

*,7,*,*,*,*,*,*,*,30,*;

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

where * marks the non-integer values of (2*h*k + k + h - 1)/8 with h >= k >= 1.

MATHEMATICA

Select[Range[200], !PrimeQ[16*# + 3]&] (* Vincenzo Librandi, Jan 13 2013 *)

PROG

(Magma) [n: n in [0..150] | not IsPrime(16*n + 3)]; // Vincenzo Librandi, Jan 13 2013

CROSSREFS

Cf. A092022.

Sequence in context: A061951 A346301 A341257 * A246647 A177729 A049993

Adjacent sequences: A153345 A153346 A153347 * A153349 A153350 A153351

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, Dec 24 2008

STATUS

approved

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Last modified December 5 13:58 EST 2022. Contains 358588 sequences. (Running on oeis4.)