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A164625
Primes p such that p+floor(p/2)+floor(p/3)+floor(p/5) is also prime.
1
2, 3, 7, 19, 83, 89, 127, 137, 139, 181, 251, 257, 311, 317, 373, 379, 449, 491, 499, 503, 509, 673, 733, 797, 853, 857, 863, 919, 971, 983, 1033, 1039, 1049, 1093, 1151, 1201, 1217, 1399, 1453, 1579, 1583, 1627, 1697, 1741, 1871, 1933, 1993, 2129, 2237, 2281
OFFSET
1,1
LINKS
EXAMPLE
For p=7, 7+3+2+1=13 is prime, which admits 7=a(4) to the sequence.
For p=19, 19+9+6+3=37 is prime, which puts 19=a(5) into the sequence.
MATHEMATICA
lst={}; Do[p=Prime[n]; If[PrimeQ[p+Floor[p/2]+Floor[p/3]+Floor[p/5]], AppendTo[lst, p]], {n, 2*6!}]; lst
Select[Prime[Range[350]], PrimeQ[Total[Floor[#/{2, 3, 5}]]+#]&] (* Harvey P. Dale, Feb 19 2012 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Comments rephrased as examples by R. J. Mathar, Aug 20 2009
STATUS
approved