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A242515
Numbers n such that 12n+1, 12n+5, 12n+7, 12n+11 are all composite numbers.
1
44, 70, 72, 74, 105, 111, 112, 132, 137, 140, 147, 154, 163, 170, 182, 193, 202, 207, 209, 235, 245, 248, 252, 258, 262, 273, 285, 312, 315, 317, 322, 329, 331, 336, 345, 347, 349, 359, 369, 372, 377, 384, 392, 397, 403, 404, 422, 427, 437
OFFSET
1,1
LINKS
EXAMPLE
a(1) = 44; 44*12+1=529, 44*12+5=533, 44*12+7=535, 44*12+11=539, and 529, 533, 535 and 539 are all composites.
MATHEMATICA
Select[Range[500], AllTrue[12#+{1, 5, 7, 11}, CompositeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Dec 13 2018 *)
PROG
(PARI)
for(i=0, 1000, if(!isprime(12*i+1) && !isprime(12*i+5) && !isprime(12*i+7) && !isprime(12*i+11), print1(i", "))) \\ Lear Young, May 16 2014
CROSSREFS
Subsequence of A153383.
Sequence in context: A111494 A092025 A250329 * A156812 A171665 A348098
KEYWORD
nonn
AUTHOR
Lear Young, May 16 2014
STATUS
approved