A258032 Primes p such that p^3 with the rightmost digit removed is also prime.

3, 17, 53, 113, 157, 233, 257, 277, 353, 359, 379, 397, 677, 877, 997, 1039, 1217, 1439, 1613, 1697, 1879, 1973, 1997, 2273, 2417, 2459, 2777, 3257, 3413, 3499, 3517, 3697, 3779, 4073, 4157, 4177, 4339, 4973, 4999, 5077, 5197, 5279, 5639, 5813, 5897, 6277, 6379

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Example

a(2) = 17 is prime: 17^3 = 4913. Removing rightmost digit gives 491 which is prime.
a(3) = 53 is prime: 53^3 = 148877. Removing rightmost digit gives 14887 which is prime.

Mathematica

Select[Prime[Range[1000]], PrimeQ[Floor[(#^3)/10]] &]

Prog

(PARI) forprime(p=1, 10000, if(isprime(floor((p^3)/10)), print1(p, ", ")))
(Magma) [p: p in PrimesUpTo(6500) |IsPrime(Floor(p^3/10))]; // Vincenzo Librandi, May 17 2015
(Haskell)
a258032 n = a258032_list !! (n-1)
a258032_list = filter ((== 1) . a010051' . flip div 10. (^ 3)) a000040_list
-- Reinhard Zumkeller, May 18 2015

Crossrefs

Cf. A000040, A024770, A052025, A137812, A227916, A227919.

Cf. A010051.

Sequence in context: A093418 A173733 A294134 * A361525 A033562 A212415

Adjacent sequences: A258029 A258030 A258031 * A258033 A258034 A258035

Keyword

nonn,base

Author

K. D. Bajpai, May 16 2015

Status

approved