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A163431
Primes p such that floor(p^3/8) is also prime.
4
3, 19, 83, 179, 191, 239, 373, 431, 643, 719, 739, 883, 1123, 1151, 1171, 1237, 1283, 1429, 1459, 1669, 1811, 2053, 2083, 2293, 2351, 2437, 2579, 2677, 2687, 2819, 2851, 2879, 3167, 3253, 3491, 3539, 3877, 4051, 4099, 4483, 4549, 4643, 4799, 5087, 5171
OFFSET
1,1
LINKS
FORMULA
A163430(n) = floor( a(n)^3/8 ).
EXAMPLE
a(1)=3 generates 3^3/8=3.375 where 3 is prime.
a(2)=19 generates 19^3/8=857.375 where 857 is prime.
MATHEMATICA
f[n_]:=IntegerPart[(p/2)^3]; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], AppendTo[lst, p]], {n, 7!}]; lst
CROSSREFS
Sequence in context: A061171 A293561 A240286 * A167242 A373681 A089621
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Mathematica specific notation removed, comments moved to examples - R. J. Mathar, Sep 17 2009
STATUS
approved