A163442 Primes of the form floor((p/3)^3), where p is prime.
181, 1103, 40471, 143329, 212419, 266261, 468493, 14586401, 20948491, 48894061, 53298877, 86546399, 136061111, 150851969, 189448891, 227353303, 249650309, 256855171, 328033129, 361451309, 507533053, 710528249, 815653171, 1172016731
Offset: 1
Keywords
Examples
(17/3)^3=181.963 -> 181, (31/3)^3=1103.37 -> 1103, (103/3)^3=40471.4 -> 40471
Links
- G. C. Greubel, Table of n, a(n) for n = 1..1000
Crossrefs
Programs
-
Mathematica
f[n_]:=IntegerPart[(p/3)^3]; lst={};Do[p=Prime[n];If[PrimeQ[f[p]],AppendTo[lst,f[p]]],{n,7!}];lst Select[Table[Floor[(p/3)^3],{p,Prime[Range[800]]}],PrimeQ] (* Harvey P. Dale, Dec 16 2017 *)
-
PARI
forprime(p=2,1e3,n=p^3\27;if(isprime(n),print1(n",")))
Extensions
Program and editing by Charles R Greathouse IV, Nov 09 2009