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A079703
Numbers 4p where p is prime and 2p+1 and 4p+1 are composite.
1
68, 76, 124, 188, 236, 244, 284, 404, 412, 428, 436, 548, 596, 604, 628, 668, 724, 788, 844, 892, 908, 916, 964, 1028, 1052, 1076, 1084, 1132, 1244, 1252, 1268, 1324, 1348, 1388, 1396, 1412, 1468, 1516, 1532, 1556, 1588, 1604, 1684, 1756, 1796, 1828, 1844
OFFSET
0,1
LINKS
EXAMPLE
2*17+1=35, 4*17+1=69, therefore 68 is in the sequence.
MATHEMATICA
Select[4*Prime[Range[90]], AllTrue[{#/2, #}+1, CompositeQ]&] (* Harvey P. Dale, Dec 28 2023 *)
PROG
(PARI) forprime (p=3, 200, if (!isprime(2*p+1) && !isprime(4*p+1), print1(4*p", ")))
CROSSREFS
Subsequence of A005277
Sequence in context: A153831 A306113 A058980 * A281235 A097760 A180937
KEYWORD
nonn
AUTHOR
Jon Perry, Jan 31 2003
EXTENSIONS
More terms from Michel Marcus, Mar 17 2014
STATUS
approved