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A258032 Primes p such that p^3 with the rightmost digit removed is also prime. 2
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 (list; graph; refs; listen; history; text; internal format)
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: A163943 A093418 A173733 * A033562 A212415 A152457

Adjacent sequences:  A258029 A258030 A258031 * A258033 A258034 A258035

KEYWORD

nonn,base

AUTHOR

K. D. Bajpai, May 16 2015

STATUS

approved

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Last modified September 21 15:30 EDT 2017. Contains 292309 sequences.