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A155511
Members of A038512 of the form k, k+2, k+6, k+8.
1
4181, 4183, 4187, 4189, 4841, 4843, 4847, 4849, 6401, 6403, 6407, 6409, 14801, 14803, 14807, 14809, 15941, 15943, 15947, 15949, 16391, 16393, 16397, 16399, 19091, 19093, 19097, 19099, 19511, 19513, 19517, 19519, 19631, 19633, 19637, 19639, 24581, 24583, 24587, 24589
OFFSET
1,1
COMMENTS
In each set of 4, k+4 (4185, 4845, 6405, etc.) is always divisible by 15.
LINKS
EXAMPLE
4841 = 47*103, 4843 = 29*167, 4847 = 37*131 and 4849 = 13*373. All are composite with no prime factor less than 13 and they form a sequence k, k+2, k+6, k+8.
MATHEMATICA
q[n_] := AllTrue[n + {0, 2, 6, 8}, CompositeQ[#] && FactorInteger[#][[1, 1]] >= 13 &]; Flatten @ Outer[Plus, Select[Range[25000], q], {0, 2, 6, 8}] (* Amiram Eldar, Mar 22 2021 *)
CROSSREFS
Cf. A038512.
Sequence in context: A308752 A179249 A045734 * A049062 A093372 A212424
KEYWORD
nonn
AUTHOR
Howard Berman (howard_berman(AT)hotmail.com), Jan 23 2009
EXTENSIONS
Missing terms inserted by Amiram Eldar, Mar 22 2021
STATUS
approved