OFFSET
1,1
COMMENTS
In each set of 4, k+4 (4185, 4845, 6405, etc.) is always divisible by 15.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
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
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